Path | Short | Definition | Comments |
---|---|---|---|
Measurements and simple assertions | Measurements and simple assertions made about a patient, device or other subject. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
code | Type of observation (code / type) | Describes what was observed. Sometimes this is called the observation "name". | *All* code-value and, if present, component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Clinically relevant time/time-period for observation | The time or time-period the observed value is asserted as being true. For biological subjects - e.g. human patients - this is usually called the "physiologically relevant time". This is usually either the time of the procedure or of specimen collection, but very often the source of the date/time is not known, only the date/time itself. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
value[x] | Actual result | The information determined as a result of making the observation, if the information has a simple value. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about the observation | Comments about the observation or the results. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Related resource that belongs to the Observation group | This observation is a group observation (e.g. a battery, a panel of tests, a set of vital sign measurements) that includes the target as a member of the group. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Component results | Some observations have multiple component observations. These component observations are expressed as separate code value pairs that share the same attributes. Examples include systolic and diastolic component observations for blood pressure measurement and multiple component observations for genetics observations. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Actual component result | The information determined as a result of making the observation, if the information has a simple value. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
This resource is an event resource from a FHIR workflow perspective - see Workflow.
Observations are a central element in healthcare, used to support diagnosis, monitor progress, determine baselines and patterns and even capture demographic characteristics. Most observations are simple name/value pair assertions with some metadata, but some observations group other observations together logically, or even are multi-component observations. Note that the DiagnosticReport resource provides a clinical or workflow context for a set of observations and the Observation resource is referenced by DiagnosticReport to represent laboratory, imaging, and other clinical and diagnostic data to form a complete report.
Uses for the Observation resource include:
*The boundaries between clinical findings and disorders remains a challenge in medical ontology. Refer the Boundaries section below and in Condition for general guidance. These boundaries can be clarified by profiling Observation for a particular use case.
The following core profiles for the Observation resource have been defined as well. If implementations use this Resource when expressing the profile-specific concepts as structured data, they SHALL conform to the following profiles:
Profile | Description |
---|---|
Vital signs | The FHIR Vital Signs profile sets minimum expectations for the Observation Resource to record, search and fetch the vital signs (e.g. temperature, blood pressure, respiration rate, etc.) associated with a patient |
At its core, Observation allows expressing a name-value pair or structured collection of name-value pairs. As such, it can support conveying any type of information desired. However, that is not its intent. Observation is intended for capturing measurements and subjective point-in-time assessments. It is not intended to be used for those specific contexts and use cases already covered by other FHIR resources. For example, the AllergyIntolerance resource represents a patient allergies, MedicationStatement resource: medications taken by a patient, FamilyMemberHistory resource: a patient's family history, Procedure resource: information about a procedure, and QuestionnaireResponse resource: a set of answers to a set of questions. The Observation resource should not be used to record clinical diagnosis about a patient or subject that are typically captured in the Condition resource or the ClinicalImpression resource. The Observation resource is often referenced by the Condition resource to provide specific subjective and objective data to support its assertions. There will however be situations of overlap. For example, a response to a question of "have you ever taken illicit drugs" could in principle be represented using MedicationStatement, but most systems would treat such an assertion as an Observation. In some cases, such as when source data is coming from an HL7 v2 feed, a system might not have information that allows it to distinguish diagnosis, allergy and other "specialized" types of observations from laboratory, vital sign and other observation types intended to be conveyed with this resource. In those circumstances, such specialized observations may also appear using this resource. Adhering to such convention is an appropriate use of Observation. If implementers are uncertain whether a proposed use of Observation is appropriate, they're encouraged to consult with implementers on chat.fhir.org implementer's stream
The Media resource captures a specific type of observation whose value is audio, video or image data. This resource is used instead of Observation to represent such forms of information as it exposes the metadata relevant for interpreting the information. See Media's boundaries section to see how Media (and Observation) differs from ImagingStudy and DocumentReference.
In contrast to the Observation resource, the DiagnosticReport resource typically includes additional clinical context and some mix of atomic results, images, imaging reports, textual and coded interpretation, and formatted representations. Laboratory reports, pathology reports, and imaging reports should be represented using the DiagnosticReport resource. The Observation resource is referenced by the DiagnosticReport to provide the atomic results for a particular investigation. "Laboratories routinely have a variable that is summative across a series of discrete variables - these are usually called 'impressions' or 'interpretations'. Sometimes they are algorithmically specified and sometimes they have the imprimatur of pathologists and they are conveyed in Observation or DiagnosticReport instead of the Clinical Impression resource. The Observation resource should not be used to record clinical diagnosis about a patient or subject as discussed above.
At its simplest, a resource instance can consist of only a code and a value, and status flag. The relevance of other properties will vary based on the type of observation. Profiles are created to provide guidance on capturing certain types of observations for a given use case. The Observation resource focuses on the level of detail captured by most systems. However, for a given use case there may be additional constraints and additional information relevant in certain circumstances. As with other resources, extensions can be used to introduce this additional complexity.
Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately. However, three attributes may be used for representing the focus of the observation if it is not the subject itself. The specimen
and bodySite
elements are used to represent measurements taken on subject samples or anatomic and morphological locations, and focus
represents specific aspect of the subject that are the point of attention such as another observation or a device implanted in a patient.
Many observations have important relationships to other observations and need to be grouped together. These structures have been defined to do this: DiagnosticReport and DiagnosticReport.result
, Observation and the elements: Observation.component
, Observation.hasMember
and Observation.derivedFrom
. The sections below provides guidance around which structure to use. Because the idea of what to group together is often highly contextual and based upon the end user's point of view, the choice of which structure to use will be driven by jurisdiction, organizational practice and context. Profiling will normally be necessary for implementation.
DiagnosticReport relates directly to an order (ServiceRequest). The DiagnosticReport.code
names the panel and serves as the grouping element, which is traditionally referred to as a "panel" or "battery" by laboratories. The DiagnosticReport.result
element references the individual observations. Several examples demonstrate observation grouping using DiagnosticReport as the grouping structure.
Observation.component
is used for any supporting result that cannot reasonably be interpreted and used outside the scope of the Observation it is a component of. Component observations may make up the separate and individual parts of the observation or may provide qualifying information to Observation.code
and may only be able to be understood in relation to the Observation.code
(for example, see the
$stats
operation). Therefore all code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. Components should only be used when there is only one method, one observation, one performer, one device, and one time. Some use cases for using this structure include:
On the other hand, any observations that are clinically relevant outside the context of being a component of another observation should be represented by separate Observation resources. For example a Body Mass Index (BMI) Observation should not contain components for height and weight because they are clinically relevant observations on their own and should be represented by separate Observation resources. See the section below on how to relate independent Observations.
Observation.hasMember
and Observation.derivedFrom
and the core extensions: Observation-sequelTo and Observation-replaces are used for any supporting result that can be interpreted and used on its own and has one or more different values for method, observation, performer, device, time, and/or error conditions. Two common use cases for using this structure are:
Observation.code
represents the "panel" code, typically Observation.value[x]
is not present, and the set of member Observations are listed in Observation.hasMember
. This structure permits nested grouping when used with DiagnosticReport (e.g. complex micro isolate and sensitivities report).
Observation.code
and Observation.value[x]
are present, and the linked observations are listed in Observation.derivedFrom
. An example of this would be a Body Mass Index (BMI) Observation where the height and weight measurements are referenced.
When a result value is a represented as a predefined concept using a code, valueCodeableConcept
is used. This element is bound to a value set comprised of a standard nomenclature such as SNOMED CT or a source system ("local") coded result values.
Results may be coded in multiple value sets based on different code systems and these may be mapped using the ConceptMap resource and/or given as additional codings directly in the element as shown in the example below.
For example the LOINC 43304-5 Chlamydia trachomatis rRNA [Presence] in Unspecified specimen by Probe and target amplification method is typically associated with coded presence/absence concepts. Using the coded value for 'negative' with a standard code translation, valueCodeableConcept
would be:
"valueCodeableConcept": { "coding": [ { "system": "http://snomed.info/sct", "code": "260385009", "display": "Negative" }, { "system": "https://acme.lab/resultcodes", "code": "NEG", "display": "Negative" } ], "text": "Negative for Chlamydia Trachomatis rRNA" }
When the data element is usually coded or the type associated with the code
element defines a coded value, use valueCodeableConcept
even if there is no appropriate code and only free text is available. For example using text only, the valueCodeableConcept
element would be:
"valueCodeableConcept": { "text": "uncoded free text result" }
When a coded answer list includes a concept code for "other" and there is a free text description of the concept, the valueCodeableConcept.text
element should be used to capture the full meaning of the source. In the example below, the answer code "Other" is provided in the valueCodeableConcept
element and the text value supplied value in the CodeableConcept.text
element.
{ "resourceType": "Observation", ... snip ... "code": { "coding": [ { "system": "http://loinc.org", "code": "74076-1", "display": "Medication or substance involved" } ] }, .. snip ... "valueCodeableConcept": { "coding": [ { "system": "http://loinc.org", "code": " LA20343-2", "display": "Other substance: PLEASE SPECIFY" } ], "text": "Other: Blue pills I found under my couch" } .. snip ... }
A recurring issue for many observation events, regardless of the particular pattern, is determining how to populate observation.code and observation.value. While this is typically straight-forward for laboratory observations, it can get blurry for other types of observations, such as findings and disorders, family history observations, etc. This discussion focuses on the way in which the coded representation of such statements is expressed using the Observation.code
and Observation.value
elements.
There are two distinct facets that are central to a FHIR Observations:
Several different ways of representing the same information exist using different combinations of the Observation.code
and Observation.value
. Unconstrained use of the alternatives presents a major challenge for computation of semantic equivalence and for safe interpretation of observations originating from different applications and users. The following four patterns could reasonably represent the same case. Considering that the Observation resource needs to support many use cases, the appropriate place to define the specific pattern is expected to be done through profiles and implementation guides as specified by the jurisdictions and/or organizations implementing FHIR:
Observation.code
represents the nature of the observation and the Observation.value
a code represents the non-numeric result value. These are two distinct facets that are central to a FHIR Observations. For example:
Observation.code
is nearly identical to 1) above, but the level of granularity is shifted from the value to code. For example:
Observation.code
is also expressed in a way that does not specify the observation action but indicates a statement about findings reduced to a single name (or term), as in the above item. In this example, the Observation.value
is present and "qualifies" the finding typically confirming or refuting it. For example:
Observation.code
is expressed in a way that does not specify the observation action but indicates a statement about findings reduced to a single name (or term). In this particular example in that context, the Observation.value
is omitted. For example:
The following list provides guidance on using codes or other observations to provide additional context that may alter how an observation is interpreted.:
If possible, use the most specific code you can
e.g.:
{ "resourceType": "Observation", ... snip ... "code": { "coding": [ { "system": "http://loinc.org", "code": "6689-4", "display": "Glucose [Mass/volume] in Blood --2 hours post meal" } ] }, ... snip ... }
Alternatively, use additional codes in Observation.code as described above.
e.g.: Observation.code = coding-1: 59408-5 Oxygen saturation in Arterial blood by Pulse oximetry, coding-2: 20564-1 Oxygen saturation in Blood
{ "resourceType": "Observation", ... snip ... "code": { "coding": [ { "system": "http://loinc.org", "code": "59408-5", "display": "Oxygen saturation in Arterial blood by Pulse oximetry" }, { "system": "http://loinc.org", "code": "20564-1", "display": "Oxygen saturation in Blood" } ] }, ... snip ... }
As described above, observations are typically grouped together to provide additional information needed for correctly understanding and interpreting the observation. As an alternative to grouping observations, extensions may be used to provide references to other observations needed for understanding and interpreting an observation.
Note:We are seeking input from the implementer community in evaluating existing Observation Extensions for this purpose
Feedback here.
value[x]
because most observations result values are never truly Boolean due to exceptional values such as "unknown", therefore they should use the CodeableConcept data type instead and select codes from http://terminology.hl7.org/ValueSet/v2-0136 (these "yes/no" concepts can be mapped to the display name "true/false" or other mutually exclusive terms that may be needed") valueQuantity
would be:
"valueQuantity": { "value": 2.0, "comparator": "<", "unit": "mmol/l", "system": "http://unitsofmeasure.org", "code": "mmol/L" }If the value was "NaN" (i.e. an error) the
valueCodeableConcept
element would be absent and dataAbsentReason
element would be:
"dataAbsentReason": { "coding": [ { "system": "http://terminology.hl7.org/CodeSystem/data-absent-reason", "code": "NaN", "display": "Not a Number" } ] }
The effectiveDateTime or effectivePeriod is the time that the observation is most relevant as an observation of the subject. For a biological subject (e.g. a human patient), this is the physiologically relevant time of the observation. In the case of an observation using a specimen, this represents the start and end of the specimen collection (e.g. 24-hour Urine Sodium), but if the collection time is sufficiently short, this is reported as a point in time value (e.g. normal venipuncture). In the case of an observation obtained directly from a subject (e.g. BP, Chest X-ray), this is the start and end time of the observation process, which again, is often reported as a single point in time.
Most common observations will only have one generic reference range. Reference ranges may be useful for laboratory tests and other measures like systolic blood pressure but will have little relevance for something like "pregnancy status". Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g. specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties.
If a measurement or test could not be completed (for example if the specimen is unsatisfactory or the provider cancelled the order), then the status value should be updated to "cancelled" and the specific details given - preferably as coded values in the dataAbsentReason or valueCodeableConcept element. Additional information may be provided in the `note` element as well. The specimen reject example demonstrates this using a coded value for unsatisfactory specimen in dataAbsentReason.
Genetic reporting makes heavy use of the DiagnosticReport and Observation resources. An implementation guide describing how to represent genetic results can be found here.
The lastn query operation meets the common need for searching for the most recent or "last known" Observations for a subject. Examples where this query could be used:
See the Last N Observations Query section in the Observation resource operations page for more information and examples
The stats operation performs a set of statistical calculations on a set of clinical measurements such as a blood pressure as stored on the server. This operation is focused on Observation resources with valueQuantity elements that have UCUM unit codes. Examples where this operation could be used:
based-on | Reference to the service request. | Observation.basedOn |
category | The classification of the type of observation | Observation.category |
combo-code | The code of the observation type or component type | Observation.code | Observation.component.code |
combo-data-absent-reason | The reason why the expected value in the element Observation.value[x] or Observation.component.value[x] is missing. | Observation.dataAbsentReason | Observation.component.dataAbsentReason |
combo-value-concept | The value or component value of the observation, if the value is a CodeableConcept | (Observation.value as CodeableConcept) | (Observation.component.value as CodeableConcept) |
combo-value-quantity | The value or component value of the observation, if the value is a Quantity, or a SampledData (just search on the bounds of the values in sampled data) | Observation.value as Quantity | Observation.value as SampledData | Observation.component.value as Quantity | Observation.component.value as SampledData |
component-code | The component code of the observation type | Observation.component.code |
component-data-absent-reason | The reason why the expected value in the element Observation.component.value[x] is missing. | Observation.component.dataAbsentReason |
component-value-concept | The value of the component observation, if the value is a CodeableConcept | (Observation.component.value as CodeableConcept) |
component-value-quantity | The value of the component observation, if the value is a Quantity, or a SampledData (just search on the bounds of the values in sampled data) | Observation.component.value as Quantity | Observation.component.value as SampledData |
data-absent-reason | The reason why the expected value in the element Observation.value[x] is missing. | Observation.dataAbsentReason |
derived-from | Related measurements the observation is made from | Observation.derivedFrom |
device | The Device that generated the observation data. | Observation.device |
focus | The focus of an observation when the focus is not the patient of record. | Observation.focus |
has-member | Related resource that belongs to the Observation group | Observation.hasMember |
method | The method used for the observation | Observation.method |
part-of | Part of referenced event | Observation.partOf |
performer | Who performed the observation | Observation.performer |
specimen | Specimen used for this observation | Observation.specimen |
status | The status of the observation | Observation.status |
subject | The subject that the observation is about | Observation.subject |
value-concept | The value of the observation, if the value is a CodeableConcept | (Observation.value as CodeableConcept) |
value-date | The value of the observation, if the value is a date or period of time | (Observation.value as dateTime) | (Observation.value as Period) |
value-quantity | The value of the observation, if the value is a Quantity, or a SampledData (just search on the bounds of the values in sampled data) | Observation.value as Quantity | Observation.value as SampledData |
value-string | The value of the observation, if the value is a string, and also searches in CodeableConcept.text | Observation.value as string | (Observation.value as CodeableConcept).text |
code-value-concept | Code and coded value parameter pair | Observation |
code-value-date | Code and date/time value parameter pair | Observation |
code-value-quantity | Code and quantity value parameter pair | Observation |
code-value-string | Code and string value parameter pair | Observation |
combo-code-value-concept | Code and coded value parameter pair, including in components | Observation | Observation.component |
combo-code-value-quantity | Code and quantity value parameter pair, including in components | Observation | Observation.component |
component-code-value-concept | Component code and component coded value parameter pair | Observation.component |
component-code-value-quantity | Component code and component quantity value parameter pair | Observation.component |
This profile describes the direct or derived, qualitative or quantitative physiological measurement, setting, or calculation data produced by a medical device or a device component.
Path | Short | Definition | Comments |
---|---|---|---|
Measurements and simple assertions | Measurements and simple assertions made about a patient, device or other subject. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
code | Type of observation (code / type) | Describes what was observed. Sometimes this is called the observation "name". | *All* code-value and, if present, component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effectiveDateTime | Clinically relevant time/time-period for observation | The time or time-period the observed value is asserted as being true. For biological subjects - e.g. human patients - this is usually called the "physiologically relevant time". This is usually either the time of the procedure or of specimen collection, but very often the source of the date/time is not known, only the date/time itself. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
value[x] | Actual result | The information determined as a result of making the observation, if the information has a simple value. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about the observation | Comments about the observation or the results. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Related resource that belongs to the Observation group | This observation is a group observation (e.g. a battery, a panel of tests, a set of vital sign measurements) that includes the target as a member of the group. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Component results | Some observations have multiple component observations. These component observations are expressed as separate code value pairs that share the same attributes. Examples include systolic and diastolic component observations for blood pressure measurement and multiple component observations for genetics observations. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Actual component result | The information determined as a result of making the observation, if the information has a simple value. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
Describes how the observation resource is used to report structured genetic test results
Path | Short | Definition | Comments |
---|---|---|---|
Measurements and simple assertions | Measurements and simple assertions made about a patient, device or other subject. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
code | Type of observation (code / type) | Describes what was observed. Sometimes this is called the observation "name". | *All* code-value and, if present, component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Clinically relevant time/time-period for observation | The time or time-period the observed value is asserted as being true. For biological subjects - e.g. human patients - this is usually called the "physiologically relevant time". This is usually either the time of the procedure or of specimen collection, but very often the source of the date/time is not known, only the date/time itself. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
value[x] | Actual result | The information determined as a result of making the observation, if the information has a simple value. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about the observation | Comments about the observation or the results. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Related resource that belongs to the Observation group | This observation is a group observation (e.g. a battery, a panel of tests, a set of vital sign measurements) that includes the target as a member of the group. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Component results | Some observations have multiple component observations. These component observations are expressed as separate code value pairs that share the same attributes. Examples include systolic and diastolic component observations for blood pressure measurement and multiple component observations for genetics observations. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Actual component result | The information determined as a result of making the observation, if the information has a simple value. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
FHIR Vital Signs Profile
Path | Short | Definition | Comments |
---|---|---|---|
FHIR Vital Signs Profile | The FHIR Vitals Signs profile sets minimum expectations for the Observation Resource to record, search and fetch the vital signs associated with a patient. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
category.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
category.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
category.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
category.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
category.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
category.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
code | Coded Responses from C-CDA Vital Sign Results | Coded Responses from C-CDA Vital Sign Results. | *All* code-value and, if present, component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Often just a dateTime for Vital Signs | Often just a dateTime for Vital Signs. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
value[x] | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about the observation | Comments about the observation or the results. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Used when reporting vital signs panel components | Used when reporting vital signs panel components. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Used when reporting systolic and diastolic blood pressure. | Used when reporting systolic and diastolic blood pressure. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Vital Sign Value recorded with UCUM | Vital Sign Value recorded with UCUM. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
FHIR Body Weight Profile
Path | Short | Definition | Comments |
---|---|---|---|
FHIR Body Weight Profile | This profile defines how to represent body weight observations in FHIR using a standard LOINC code and UCUM units of measure. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
category.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
category.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
category.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
category.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
category.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
category.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
code | Body Weight | Body Weight. | additional codes that translate or map to this code are allowed. For example a more granular LOINC code or code that is used locally in a system. |
code.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
code.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
code.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
code.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
code.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
code.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Often just a dateTime for Vital Signs | Often just a dateTime for Vital Signs. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
value[x] | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
value[x].id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
value[x].extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
value[x].value | Numerical value (with implicit precision) | The value of the measured amount. The value includes an implicit precision in the presentation of the value. | The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books). |
value[x].comparator | < | <= | >= | > - how to understand the value | How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value. | |
value[x].unit | Unit representation | A human-readable form of the unit. | |
value[x].system | System that defines coded unit form | The identification of the system that provides the coded form of the unit. | |
value[x].code | Coded responses from the common UCUM units for vital signs value set. | Coded responses from the common UCUM units for vital signs value set. | The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about the observation | Comments about the observation or the results. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Used when reporting vital signs panel components | Used when reporting vital signs panel components. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Used when reporting systolic and diastolic blood pressure. | Used when reporting systolic and diastolic blood pressure. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Vital Sign Value recorded with UCUM | Vital Sign Value recorded with UCUM. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
FHIR Vital Signs Panel Profile
Path | Short | Definition | Comments |
---|---|---|---|
FHIR Vital Signs Panel Profile | This profile defines the top-level grouping structure for a set of vital signs. It has no value in Observation.valueQuantity ; instead, it just includes related links (with type=has-member) to the Observations in this set (e.g. respiratory rate, heart rate, BP). | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
category.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
category.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
category.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
category.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
category.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
category.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
code | Vital Signs Panel | Vital Signs Panel. | additional codes that translate or map to this code are allowed. For example a more granular LOINC code or code that is used locally in a system. |
code.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
code.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
code.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
code.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
code.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
code.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Often just a dateTime for Vital Signs | Often just a dateTime for Vital Signs. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
value[x] | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about the observation | Comments about the observation or the results. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Used when reporting vital signs panel components | Used when reporting vital signs panel components. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Used when reporting systolic and diastolic blood pressure. | Used when reporting systolic and diastolic blood pressure. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Vital Sign Value recorded with UCUM | Vital Sign Value recorded with UCUM. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
FHIR Body Height Profile
Path | Short | Definition | Comments |
---|---|---|---|
FHIR Body Height Profile | This profile defines how to represent Body Height observations in FHIR using a standard LOINC code and UCUM units of measure. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
category.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
category.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
category.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
category.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
category.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
category.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
code | Body Height | Body Height. | additional codes that translate or map to this code are allowed. For example a more granular LOINC code or code that is used locally in a system. |
code.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
code.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
code.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
code.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
code.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
code.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Often just a dateTime for Vital Signs | Often just a dateTime for Vital Signs. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
value[x] | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
value[x].id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
value[x].extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
value[x].value | Numerical value (with implicit precision) | The value of the measured amount. The value includes an implicit precision in the presentation of the value. | The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books). |
value[x].comparator | < | <= | >= | > - how to understand the value | How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value. | |
value[x].unit | Unit representation | A human-readable form of the unit. | |
value[x].system | System that defines coded unit form | The identification of the system that provides the coded form of the unit. | |
value[x].code | Coded responses from the common UCUM units for vital signs value set. | Coded responses from the common UCUM units for vital signs value set. | The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about the observation | Comments about the observation or the results. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Used when reporting vital signs panel components | Used when reporting vital signs panel components. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Used when reporting systolic and diastolic blood pressure. | Used when reporting systolic and diastolic blood pressure. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Vital Sign Value recorded with UCUM | Vital Sign Value recorded with UCUM. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
FHIR Respiratory Rate Profile
Path | Short | Definition | Comments |
---|---|---|---|
FHIR Respiratory Rate Profile | This profile defines how to represent Respiratory Rate observations in FHIR using a standard LOINC code and UCUM units of measure. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
category.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
category.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
category.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
category.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
category.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
category.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
code | Respiratory Rate | Respiratory Rate. | additional codes that translate or map to this code are allowed. For example a more granular LOINC code or code that is used locally in a system. |
code.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
code.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
code.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
code.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
code.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
code.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Often just a dateTime for Vital Signs | Often just a dateTime for Vital Signs. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
value[x] | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
value[x].id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
value[x].extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
value[x].value | Numerical value (with implicit precision) | The value of the measured amount. The value includes an implicit precision in the presentation of the value. | The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books). |
value[x].comparator | < | <= | >= | > - how to understand the value | How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value. | |
value[x].unit | Unit representation | A human-readable form of the unit. | |
value[x].system | System that defines coded unit form | The identification of the system that provides the coded form of the unit. | |
value[x].code | Coded responses from the common UCUM units for vital signs value set. | Coded responses from the common UCUM units for vital signs value set. | The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about the observation | Comments about the observation or the results. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Used when reporting vital signs panel components | Used when reporting vital signs panel components. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Used when reporting systolic and diastolic blood pressure. | Used when reporting systolic and diastolic blood pressure. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Vital Sign Value recorded with UCUM | Vital Sign Value recorded with UCUM. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
FHIR Heart Rate Profile
Path | Short | Definition | Comments |
---|---|---|---|
FHIR Heart Rate Profile | This profile defines how to represent heart rate observations in FHIR using a standard LOINC code and UCUM units of measure. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
category.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
category.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
category.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
category.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
category.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
category.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
code | Heart Rate | Heart Rate. | additional codes that translate or map to this code are allowed. For example a more granular LOINC code or code that is used locally in a system. |
code.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
code.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
code.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
code.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
code.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
code.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Often just a dateTime for Vital Signs | Often just a dateTime for Vital Signs. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
value[x] | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
value[x].id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
value[x].extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
value[x].value | Numerical value (with implicit precision) | The value of the measured amount. The value includes an implicit precision in the presentation of the value. | The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books). |
value[x].comparator | < | <= | >= | > - how to understand the value | How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value. | |
value[x].unit | Unit representation | A human-readable form of the unit. | |
value[x].system | System that defines coded unit form | The identification of the system that provides the coded form of the unit. | |
value[x].code | Coded responses from the common UCUM units for vital signs value set. | Coded responses from the common UCUM units for vital signs value set. | The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about the observation | Comments about the observation or the results. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Used when reporting vital signs panel components | Used when reporting vital signs panel components. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Used when reporting systolic and diastolic blood pressure. | Used when reporting systolic and diastolic blood pressure. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Vital Sign Value recorded with UCUM | Vital Sign Value recorded with UCUM. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
FHIR Body Temperature Profile
Path | Short | Definition | Comments |
---|---|---|---|
FHIR Body Temperature Profile | This profile defines how to represent Body Temperature observations in FHIR using a standard LOINC code and UCUM units of measure. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
category.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
category.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
category.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
category.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
category.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
category.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
code | Body Temperature | Body Temperature. | additional codes that translate or map to this code are allowed. For example a more granular LOINC code or code that is used locally in a system. |
code.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
code.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
code.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
code.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
code.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
code.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Often just a dateTime for Vital Signs | Often just a dateTime for Vital Signs. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
value[x] | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
value[x].id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
value[x].extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
value[x].value | Numerical value (with implicit precision) | The value of the measured amount. The value includes an implicit precision in the presentation of the value. | The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books). |
value[x].comparator | < | <= | >= | > - how to understand the value | How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value. | |
value[x].unit | Unit representation | A human-readable form of the unit. | |
value[x].system | System that defines coded unit form | The identification of the system that provides the coded form of the unit. | |
value[x].code | Coded responses from the common UCUM units for vital signs value set. | Coded responses from the common UCUM units for vital signs value set. | The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about the observation | Comments about the observation or the results. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Used when reporting vital signs panel components | Used when reporting vital signs panel components. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Used when reporting systolic and diastolic blood pressure. | Used when reporting systolic and diastolic blood pressure. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Vital Sign Value recorded with UCUM | Vital Sign Value recorded with UCUM. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
FHIR Head Circumference Profile
Path | Short | Definition | Comments |
---|---|---|---|
FHIR Head Circumference Profile | This profile defines how to represent Head Circumference observations in FHIR using a standard LOINC code and UCUM units of measure. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
category.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
category.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
category.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
category.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
category.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
category.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
code | Head Circumference | Head Circumference. | additional codes that translate or map to this code are allowed. For example a more granular LOINC code or code that is used locally in a system. |
code.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
code.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
code.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
code.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
code.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
code.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Often just a dateTime for Vital Signs | Often just a dateTime for Vital Signs. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
value[x] | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
value[x].id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
value[x].extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
value[x].value | Numerical value (with implicit precision) | The value of the measured amount. The value includes an implicit precision in the presentation of the value. | The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books). |
value[x].comparator | < | <= | >= | > - how to understand the value | How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value. | |
value[x].unit | Unit representation | A human-readable form of the unit. | |
value[x].system | System that defines coded unit form | The identification of the system that provides the coded form of the unit. | |
value[x].code | Coded responses from the common UCUM units for vital signs value set. | Coded responses from the common UCUM units for vital signs value set. | The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about the observation | Comments about the observation or the results. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Used when reporting vital signs panel components | Used when reporting vital signs panel components. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Used when reporting systolic and diastolic blood pressure. | Used when reporting systolic and diastolic blood pressure. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Vital Sign Value recorded with UCUM | Vital Sign Value recorded with UCUM. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
FHIR Oxygen Saturation Profile
Path | Short | Definition | Comments |
---|---|---|---|
FHIR Oxygen Saturation Profile | This profile defines how to represent Oxygen Saturation observations in FHIR using a standard LOINC code and UCUM units of measure. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
category.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
category.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
category.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
category.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
category.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
category.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
code | Oxygen Saturation | Oxygen Saturation. | additional codes that translate or map to this code are allowed. For example a more granular LOINC code or code that is used locally in a system. |
code.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
code.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
code.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
code.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
code.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
code.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Often just a dateTime for Vital Signs | Often just a dateTime for Vital Signs. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
value[x] | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
value[x].id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
value[x].extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
value[x].value | Numerical value (with implicit precision) | The value of the measured amount. The value includes an implicit precision in the presentation of the value. | The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books). |
value[x].comparator | < | <= | >= | > - how to understand the value | How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value. | |
value[x].unit | Unit representation | A human-readable form of the unit. | |
value[x].system | System that defines coded unit form | The identification of the system that provides the coded form of the unit. | |
value[x].code | Coded responses from the common UCUM units for vital signs value set. | Coded responses from the common UCUM units for vital signs value set. | The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about the observation | Comments about the observation or the results. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Used when reporting vital signs panel components | Used when reporting vital signs panel components. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Used when reporting systolic and diastolic blood pressure. | Used when reporting systolic and diastolic blood pressure. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Vital Sign Value recorded with UCUM | Vital Sign Value recorded with UCUM. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
FHIR Body Mass Index (BMI) Profile
Path | Short | Definition | Comments |
---|---|---|---|
FHIR Body Mass Index (BMI) Profile | This profile defines how to represent Body Mass Index (BMI) observations in FHIR using a standard LOINC code and UCUM units of measure. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
category.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
category.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
category.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
category.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
category.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
category.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
code | Body Mass Index (BMI) | Body Mass Index (BMI). | additional codes that translate or map to this code are allowed. For example a more granular LOINC code or code that is used locally in a system. |
code.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
code.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
code.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
code.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
code.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
code.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Often just a dateTime for Vital Signs | Often just a dateTime for Vital Signs. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
value[x] | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
value[x].id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
value[x].extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
value[x].value | Numerical value (with implicit precision) | The value of the measured amount. The value includes an implicit precision in the presentation of the value. | The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books). |
value[x].comparator | < | <= | >= | > - how to understand the value | How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value. | |
value[x].unit | Unit representation | A human-readable form of the unit. | |
value[x].system | System that defines coded unit form | The identification of the system that provides the coded form of the unit. | |
value[x].code | Coded responses from the common UCUM units for vital signs value set. | Coded responses from the common UCUM units for vital signs value set. | The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about the observation | Comments about the observation or the results. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Used when reporting vital signs panel components | Used when reporting vital signs panel components. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Used when reporting systolic and diastolic blood pressure. | Used when reporting systolic and diastolic blood pressure. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Vital Sign Value recorded with UCUM | Vital Sign Value recorded with UCUM. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
FHIR Blood Pressure Profile
Path | Short | Definition | Comments |
---|---|---|---|
FHIR Blood Pressure Profile | This profile defines how to represent Blood Pressure observations in FHIR using a standard LOINC code and UCUM units of measure. This is a grouping structure. It has no value in Observation.valueQuantity but contains at least one component (systolic and/or diastolic). | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
category.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
category.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
category.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
category.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
category.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
category.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
category.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
category.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
category.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
code | Blood Pressure | Blood Pressure. | additional codes that translate or map to this code are allowed. For example a more granular LOINC code or code that is used locally in a system. |
code.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding | Code defined by a terminology system | A reference to a code defined by a terminology system. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
code.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
code.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
code.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
code.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
code.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
code.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
code.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
code.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Often just a dateTime for Vital Signs | Often just a dateTime for Vital Signs. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
value[x] | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about the observation | Comments about the observation or the results. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Used when reporting vital signs panel components | Used when reporting vital signs panel components. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Used when reporting systolic and diastolic blood pressure. | Used when reporting systolic and diastolic blood pressure. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Vital Sign Value recorded with UCUM | Vital Sign Value recorded with UCUM. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
component | Used when reporting systolic and diastolic blood pressure. | Used when reporting systolic and diastolic blood pressure. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | additional codes that translate or map to this code are allowed. For example a more granular LOINC code or code that is used locally in a system. |
component.code.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.code.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code.coding | Systolic Blood Pressure | Systolic Blood Pressure. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
component.code.coding | Systolic Blood Pressure | Systolic Blood Pressure. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
component.code.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.code.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
component.code.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
component.code.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
component.code.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
component.code.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
component.code.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
component.valueQuantity | Vital Sign Value recorded with UCUM | Vital Sign Value recorded with UCUM. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.valueQuantity.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.valueQuantity.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.valueQuantity.value | Numerical value (with implicit precision) | The value of the measured amount. The value includes an implicit precision in the presentation of the value. | The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books). |
component.valueQuantity.comparator | < | <= | >= | > - how to understand the value | How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value. | |
component.valueQuantity.unit | Unit representation | A human-readable form of the unit. | |
component.valueQuantity.system | System that defines coded unit form | The identification of the system that provides the coded form of the unit. | |
component.valueQuantity.code | Coded responses from the common UCUM units for vital signs value set. | Coded responses from the common UCUM units for vital signs value set. | The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
component | Used when reporting systolic and diastolic blood pressure. | Used when reporting systolic and diastolic blood pressure. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | additional codes that translate or map to this code are allowed. For example a more granular LOINC code or code that is used locally in a system. |
component.code.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.code.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code.coding | Diastolic Blood Pressure | Diastolic Blood Pressure. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
component.code.coding | Diastolic Blood Pressure | Diastolic Blood Pressure. | Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. |
component.code.coding.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.code.coding.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code.coding.system | Identity of the terminology system | The identification of the code system that defines the meaning of the symbol in the code. | The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. |
component.code.coding.version | Version of the system - if relevant | The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. | Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. |
component.code.coding.code | Symbol in syntax defined by the system | A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). | |
component.code.coding.display | Representation defined by the system | A representation of the meaning of the code in the system, following the rules of the system. | |
component.code.coding.userSelected | If this coding was chosen directly by the user | Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). | Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. |
component.code.text | Plain text representation of the concept | A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. | Very often the text is the same as a displayName of one of the codings. |
component.valueQuantity | Vital Sign Value recorded with UCUM | Vital Sign Value recorded with UCUM. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.valueQuantity.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.valueQuantity.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.valueQuantity.value | Numerical value (with implicit precision) | The value of the measured amount. The value includes an implicit precision in the presentation of the value. | The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books). |
component.valueQuantity.comparator | < | <= | >= | > - how to understand the value | How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value. | |
component.valueQuantity.unit | Unit representation | A human-readable form of the unit. | |
component.valueQuantity.system | System that defines coded unit form | The identification of the system that provides the coded form of the unit. | |
component.valueQuantity.code | Coded responses from the common UCUM units for vital signs value set. | Coded responses from the common UCUM units for vital signs value set. | The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
Describes how the lab report is used for a standard Lipid Profile - Cholesterol, Triglyceride and Cholesterol fractions. Uses LOINC codes
Path | Short | Definition | Comments |
---|---|---|---|
Measurements and simple assertions | Measurements and simple assertions made about a patient, device or other subject. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
code | Cholesterol | Cholesterol. | *All* code-value and, if present, component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Clinically relevant time/time-period for observation | The time or time-period the observed value is asserted as being true. For biological subjects - e.g. human patients - this is usually called the "physiologically relevant time". This is usually either the time of the procedure or of specimen collection, but very often the source of the date/time is not known, only the date/time itself. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
valueQuantity | Cholesterol value | Cholesterol value. If a result is not available, use the comments field. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
valueQuantity.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
valueQuantity.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
valueQuantity.value | Actual numerical value | Actual numerical value. | The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books). |
valueQuantity.comparator | < | <= | >= | > - how to understand the value | How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value. | No need for this on cholesterol. |
valueQuantity.unit | Unit representation | A human-readable form of the unit. | |
valueQuantity.system | System that defines coded unit form | The identification of the system that provides the coded form of the unit. | |
valueQuantity.code | Coded form of the unit | A computer processable form of the unit in some unit representation system. | The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | + | ++ | +++ | - | -- | --- | + | ++ | +++ | - | -- | ---. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about result | May include statements about significant, unexpected or unreliable. values, or information about the source of the value where this may be relevant to the interpretation of the result. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | A fixed quantity (no comparator) | <4.5 mmol/L. | Per Australian NHF Recommendations. |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Related resource that belongs to the Observation group | This observation is a group observation (e.g. a battery, a panel of tests, a set of vital sign measurements) that includes the target as a member of the group. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Component results | Some observations have multiple component observations. These component observations are expressed as separate code value pairs that share the same attributes. Examples include systolic and diastolic component observations for blood pressure measurement and multiple component observations for genetics observations. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Actual component result | The information determined as a result of making the observation, if the information has a simple value. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
Triglyceride Result
Path | Short | Definition | Comments |
---|---|---|---|
Triglyceride Result | Group of elements for Triglyceride result. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
code | Triglyceride | Triglyceride. | *All* code-value and, if present, component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Clinically relevant time/time-period for observation | The time or time-period the observed value is asserted as being true. For biological subjects - e.g. human patients - this is usually called the "physiologically relevant time". This is usually either the time of the procedure or of specimen collection, but very often the source of the date/time is not known, only the date/time itself. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
valueQuantity | Triglyceride value | Triglyceride value. If a result is not available, use the comments field. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | + | ++ | +++ | - | -- | --- | + | ++ | +++ | - | -- | ---. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about result | Comments about result. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | Per Australian NHF Recommendations. |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Related resource that belongs to the Observation group | This observation is a group observation (e.g. a battery, a panel of tests, a set of vital sign measurements) that includes the target as a member of the group. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Component results | Some observations have multiple component observations. These component observations are expressed as separate code value pairs that share the same attributes. Examples include systolic and diastolic component observations for blood pressure measurement and multiple component observations for genetics observations. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Actual component result | The information determined as a result of making the observation, if the information has a simple value. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
HDL Cholesterol Result
Path | Short | Definition | Comments |
---|---|---|---|
HDL Cholesterol Result | Group of elements for HDL Cholesterol result. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
code | HDL Cholesterol | HDL Cholesterol. | *All* code-value and, if present, component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Clinically relevant time/time-period for observation | The time or time-period the observed value is asserted as being true. For biological subjects - e.g. human patients - this is usually called the "physiologically relevant time". This is usually either the time of the procedure or of specimen collection, but very often the source of the date/time is not known, only the date/time itself. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
valueQuantity | HDL Cholesterol value | HDL Cholesterol value. If a result is not available, use the comments field. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | + | ++ | +++ | - | -- | --- | + | ++ | +++ | - | -- | ---. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about result | Comments about result. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | A fixed quantity (no comparator) | >1.5 mmol/L. | The context of use may frequently define what kind of quantity this is and therefore what kind of units can be used. The context of use may also restrict the values for the comparator. |
referenceRange.high | High Range, if relevant | The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). | Per Australian NHF Recommendations. |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Related resource that belongs to the Observation group | This observation is a group observation (e.g. a battery, a panel of tests, a set of vital sign measurements) that includes the target as a member of the group. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Component results | Some observations have multiple component observations. These component observations are expressed as separate code value pairs that share the same attributes. Examples include systolic and diastolic component observations for blood pressure measurement and multiple component observations for genetics observations. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Actual component result | The information determined as a result of making the observation, if the information has a simple value. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
LDL Cholesterol Result
Path | Short | Definition | Comments |
---|---|---|---|
LDL Cholesterol Result | Group of elements for LDL Cholesterol result. | Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. | |
identifier | Business Identifier for observation | A unique identifier assigned to this observation. | |
basedOn | Fulfills plan, proposal or order | A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. | |
partOf | Part of referenced event | A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. | To link an Observation to an Encounter use `encounter`. See the [Notes](observation.html#obsgrouping) below for guidance on referencing another Observation. |
status | registered | preliminary | final | amended + | The status of the result value. | This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. |
category | Classification of type of observation | A code that classifies the general type of observation being made. | In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. |
code | LDL Cholesterol -measured or calculated per code | LDL Cholesterol -measured or calculated per code. | *All* code-value and, if present, component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
subject | Who and/or what the observation is about | The patient, or group of patients, location, or device this observation is about and into whose record the observation is placed. If the actual focus of the observation is different from the subject (or a sample of, part, or region of the subject), the `focus` element or the `code` itself specifies the actual focus of the observation. | One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. |
focus | What the observation is about, when it is not about the subject of record | The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. | Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension [focusCode](extension-observation-focuscode.html). |
encounter | Healthcare event during which this observation is made | The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. | This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). |
effective[x] | Clinically relevant time/time-period for observation | The time or time-period the observed value is asserted as being true. For biological subjects - e.g. human patients - this is usually called the "physiologically relevant time". This is usually either the time of the procedure or of specimen collection, but very often the source of the date/time is not known, only the date/time itself. | At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the [Timing](datatypes.html#timing) datatype which allow the measurement to be tied to regular life events. |
issued | Date/Time this version was made available | The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. | For Observations that don’t require review and verification, it may be the same as the [`lastUpdated` ](resource-definitions.html#Meta.lastUpdated) time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. |
performer | Who is responsible for the observation | Who was responsible for asserting the observed value as "true". | |
valueQuantity | LDL Cholesterol value | LDL Cholesterol value. If a result is not available, use the comments field. | An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
dataAbsentReason | Why the result is missing | Provides a reason why the expected value in the element Observation.value[x] is missing. | Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. |
interpretation | + | ++ | +++ | - | -- | --- | + | ++ | +++ | - | -- | ---. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
note | Comments about result | Comments about result. | May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. |
bodySite | Observed body part | Indicates the site on the subject's body where the observation was made (i.e. the target site). | Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension[ bodySite](extension-bodysite.html). |
method | How it was done | Indicates the mechanism used to perform the observation. | Only used if not implicit in code for Observation.code. |
specimen | Specimen used for this observation | The specimen that was used when this observation was made. | Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). |
device | (Measurement) Device | The device used to generate the observation data. | Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. |
referenceRange | Provides guide for interpretation | Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |
referenceRange.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
referenceRange.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
referenceRange.low | Low Range, if relevant | The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). | |
referenceRange.high | A fixed quantity (no comparator) | <3.0 mmol/L. | Per Australian NHF Recommendations. |
referenceRange.type | Reference range qualifier | Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. | This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. |
referenceRange.appliesTo | Reference range population | Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. | This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. |
referenceRange.age | Applicable age range, if relevant | The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. | |
referenceRange.text | Text based reference range in an observation | Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". | |
hasMember | Related resource that belongs to the Observation group | This observation is a group observation (e.g. a battery, a panel of tests, a set of vital sign measurements) that includes the target as a member of the group. | When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. Note that a system may calculate results from [QuestionnaireResponse](questionnaireresponse.html) into a final score and represent the score as an Observation. |
derivedFrom | Related measurements the observation is made from | The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. | All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see [Notes](observation.html#obsgrouping) below. |
component | Component results | Some observations have multiple component observations. These component observations are expressed as separate code value pairs that share the same attributes. Examples include systolic and diastolic component observations for blood pressure measurement and multiple component observations for genetics observations. | For a discussion on the ways Observations can be assembled in groups together see [Notes](observation.html#notes) below. |
component.id | Unique id for inter-element referencing | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. | |
component.extension | Additional content defined by implementations | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.modifierExtension | Extensions that cannot be ignored even if unrecognized | May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself). | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
component.code | Type of component observation (code / type) | Describes what was observed. Sometimes this is called the observation "code". | *All* code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. |
component.value[x] | Actual component result | The information determined as a result of making the observation, if the information has a simple value. | Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the [Notes section](observation.html#notes) below. |
component.dataAbsentReason | Why the component result is missing | Provides a reason why the expected value in the element Observation.component.value[x] is missing. | "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. |
component.interpretation | High, low, normal, etc. | A categorical assessment of an observation value. For example, high, low, normal. | Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. |
component.referenceRange | Provides guide for interpretation of component result | Guidance on how to interpret the value by comparison to a normal or recommended range. | Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. |