Nictiz FHIR NL STU3 Zib2017
1.3.15 - CI Build

Nictiz FHIR NL STU3 Zib2017 - Local Development build (v1.3.15) built by the FHIR (HL7® FHIR® Standard) Build Tools. See the Directory of published versions

Resource Profile: nl-core-observation - Detailed Descriptions

Active as of 2024-04-09

Definitions for the nl-core-observation resource profile.

Guidance on how to interpret the contents of this table can be found here

0. Observation
2. Observation.identifier
NoteThis is a business identifier, not a resource identifier (see discussion)
4. Observation.subject
Control1..?
TypeReference(Group, Device, nl-core-location, nl-core-patient)
6. Observation.context
TypeReference(nl-core-episodeofcare, HCIM Encounter, gp-Encounter)
8. Observation.effective[x]
[x] NoteSee Choice of Data Types for further information about how to use [x]
10. Observation.performer
TypeReference(nl-core-organization, nl-core-patient, nl-core-practitioner, nl-core-relatedperson)
12. Observation.performer.extension
SlicingThis element introduces a set of slices on Observation.performer.extension. The slices are unordered and Open, and can be differentiated using the following discriminators:
  • value @ url
  • 14. Observation.performer.extension:practitionerRole
    Slice NamepractitionerRole
    Control0..1
    TypeExtension(PractitionerRole Reference) (Extension Type: Reference)

    Guidance on how to interpret the contents of this table can be found here

    0. Observation
    Definition

    Measurements and simple assertions made about a patient, device or other subject.

    ShortMeasurements and simple assertions
    Comments

    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 lab reports, etc.

    Control0..*
    Alternate NamesVital Signs, Measurement, Results, Tests
    Invariantsdom-2: If the resource is contained in another resource, it SHALL NOT contain nested Resources (contained.contained.empty())
    dom-1: If the resource is contained in another resource, it SHALL NOT contain any narrative (contained.text.empty())
    dom-4: If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated (contained.meta.versionId.empty() and contained.meta.lastUpdated.empty())
    dom-3: If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource (contained.where(('#'+id in %resource.descendants().reference).not()).empty())
    obs-7: If code is the same as a component code then the value element associated with the code SHALL NOT be present (value.empty() or component.code.where( (coding.code = %resource.code.coding.code) and (coding.system = %resource.code.coding.system)).empty())
    obs-6: dataAbsentReason SHALL only be present if Observation.value[x] is not present (dataAbsentReason.empty() or value.empty())
    dom-2: If the resource is contained in another resource, it SHALL NOT contain nested Resources (contained.contained.empty())
    dom-1: If the resource is contained in another resource, it SHALL NOT contain any narrative (contained.text.empty())
    dom-4: If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated (contained.meta.versionId.empty() and contained.meta.lastUpdated.empty())
    dom-3: If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource (contained.where(('#'+id in %resource.descendants().reference).not()).empty())
    obs-7: If code is the same as a component code then the value element associated with the code SHALL NOT be present (value.empty() or component.code.where( (coding.code = %resource.code.coding.code) and (coding.system = %resource.code.coding.system)).empty())
    obs-6: dataAbsentReason SHALL only be present if Observation.value[x] is not present (dataAbsentReason.empty() or value.empty())
    2. Observation.implicitRules
    Definition

    A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content.

    ShortA set of rules under which this content was created
    Comments

    Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element.

    This element is labelled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation.

    Control0..1
    Typeuri
    Is Modifiertrue because No Modifier Reason provideed in previous versions of FHIR
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summarytrue
    4. Observation.modifierExtension
    Definition

    May be used to represent additional information that is not part of the basic definition of the resource, and that modifies the understanding of the element that contains it. Usually modifier elements provide negation or qualification. In order 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 is allowed to 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.

    ShortExtensions that cannot be ignored
    Comments

    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.

    Control0..*
    TypeExtension
    Is Modifiertrue because No Modifier Reason provideed in previous versions of FHIR
    Alternate Namesextensions, user content
    6. Observation.identifier
    Definition

    A unique identifier assigned to this observation.

    ShortBusiness Identifier for observation
    NoteThis is a business identifier, not a resource identifier (see discussion)
    Control0..*
    TypeIdentifier
    Summarytrue
    Requirements

    Allows observations to be distinguished and referenced.

    8. Observation.status
    Definition

    The status of the result value.

    Shortregistered | preliminary | final | amended +
    Comments

    This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid.

    Control1..1
    BindingThe codes SHALL be taken from ObservationStatushttp://hl7.org/fhir/ValueSet/observation-status
    (required to http://hl7.org/fhir/ValueSet/observation-status)

    Codes providing the status of an observation.

    Typecode
    Is Modifiertrue because No Modifier Reason provideed in previous versions of FHIR
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summarytrue
    Requirements

    Need to track the status of individual results. Some results are finalized before the whole report is finalized.

    10. Observation.code
    Definition

    Describes what was observed. Sometimes this is called the observation "name".

    ShortType of observation (code / type)
    Control1..1
    BindingFor example codes, see LOINC Codeshttp://hl7.org/fhir/ValueSet/observation-codes
    (example to http://hl7.org/fhir/ValueSet/observation-codes)

    Codes identifying names of simple observations.

    TypeCodeableConcept
    Summarytrue
    Requirements

    Knowing what kind of observation is being made is essential to understanding the observation.

    Alternate NamesName
    12. Observation.subject
    Definition

    The patient, or group of patients, location, or device whose characteristics (direct or indirect) are described by the observation and into whose record the observation is placed. Comments: Indirect characteristics may be those of a specimen, fetus, donor, other observer (for example a relative or EMT), or any observation made about the subject.

    ShortWho and/or what this is about
    Comments

    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.

    If the target of the observation is different than the subject, the general extension observation-focal-subject. may be used. However, the distinction between the patient's own value for an observation versus that of the fetus, or the donor or blood product unit, etc., are often specified in the observation code.

    Control10..1
    TypeReference(Group, Device, nl-core-location, nl-core-patient, Patient, Location)
    Summarytrue
    Requirements

    Observations have no value if you don't know who or what they're about.

    14. Observation.context
    Definition

    The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made.

    ShortHealthcare event during which this observation is made
    Comments

    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 or episode but still be tied to the context of the encounter or episode (e.g. pre-admission lab tests).

    Control0..1
    TypeReference(nl-core-episodeofcare, HCIM Encounter, gp-Encounter, Encounter, EpisodeOfCare)
    Requirements

    For some observations it may be important to know the link between an observation and a particular encounter.

    Alternate NamesEncounter
    16. Observation.effective[x]
    Definition

    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.

    ShortClinically relevant time/time-period for observation
    Comments

    At least a date should be present unless this observation is a historical report.

    Control0..1
    TypeChoice of: dateTime, Period
    [x] NoteSee Choice of Data Types for further information about how to use [x]
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summarytrue
    Requirements

    Knowing when an observation was deemed true is important to its relevance as well as determining trends.

    Alternate NamesOccurrence
    18. Observation.performer
    Definition

    Who was responsible for asserting the observed value as "true".

    ShortWho is responsible for the observation
    Control0..*
    TypeReference(nl-core-organization, nl-core-patient, nl-core-practitioner, nl-core-relatedperson, Practitioner, Organization, Patient, RelatedPerson)
    Summarytrue
    Requirements

    May give a degree of confidence in the observation and also indicates where follow-up questions should be directed.

    20. Observation.performer.extension
    Definition

    An Extension


    May be used to represent additional information that is not part of the basic definition of the element. In order 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 is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

    ShortExtensionAdditional Content defined by implementations
    Comments

    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.

    Control0..*
    TypeExtension
    Alternate Namesextensions, user content
    SlicingThis element introduces a set of slices on Observation.performer.extension. The slices are unordered and Open, and can be differentiated using the following discriminators:
    • value @ url
    • 22. Observation.performer.extension:practitionerRole
      Slice NamepractitionerRole
      Definition

      Optional Extension Element - found in all resources.

      ShortOptional Extensions Element
      Control0..1
      TypeExtension(PractitionerRole Reference) (Extension Type: Reference)

      Guidance on how to interpret the contents of this table can be found here

      0. Observation
      Definition

      Measurements and simple assertions made about a patient, device or other subject.

      ShortMeasurements and simple assertions
      Comments

      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 lab reports, etc.

      Control0..*
      Alternate NamesVital Signs, Measurement, Results, Tests
      Invariantsdom-2: If the resource is contained in another resource, it SHALL NOT contain nested Resources (contained.contained.empty())
      dom-1: If the resource is contained in another resource, it SHALL NOT contain any narrative (contained.text.empty())
      dom-4: If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated (contained.meta.versionId.empty() and contained.meta.lastUpdated.empty())
      dom-3: If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource (contained.where(('#'+id in %resource.descendants().reference).not()).empty())
      obs-7: If code is the same as a component code then the value element associated with the code SHALL NOT be present (value.empty() or component.code.where( (coding.code = %resource.code.coding.code) and (coding.system = %resource.code.coding.system)).empty())
      obs-6: dataAbsentReason SHALL only be present if Observation.value[x] is not present (dataAbsentReason.empty() or value.empty())
      2. Observation.id
      Definition

      The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes.

      ShortLogical id of this artifact
      Comments

      The only time that a resource does not have an id is when it is being submitted to the server using a create operation.

      Control0..1
      Typeid
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Summarytrue
      4. Observation.meta
      Definition

      The metadata about the resource. This is content that is maintained by the infrastructure. Changes to the content may not always be associated with version changes to the resource.

      ShortMetadata about the resource
      Control0..1
      TypeMeta
      Summarytrue
      6. Observation.implicitRules
      Definition

      A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content.

      ShortA set of rules under which this content was created
      Comments

      Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element.

      This element is labelled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation.

      Control0..1
      Typeuri
      Is Modifiertrue because No Modifier Reason provideed in previous versions of FHIR
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Summarytrue
      8. Observation.language
      Definition

      The base language in which the resource is written.

      ShortLanguage of the resource content
      Comments

      Language is provided to support indexing and accessibility (typically, services such as text to speech use the language tag). The html language tag in the narrative applies to the narrative. The language tag on the resource may be used to specify the language of other presentations generated from the data in the resource Not all the content has to be in the base language. The Resource.language should not be assumed to apply to the narrative automatically. If a language is specified, it should it also be specified on the div element in the html (see rules in HTML5 for information about the relationship between xml:lang and the html lang attribute).

      Control0..1
      BindingUnless not suitable, these codes SHALL be taken from Common Languages
      (extensible to http://hl7.org/fhir/ValueSet/languages)

      A human language.

      Additional BindingsPurpose
      AllLanguagesMax Binding
      Typecode
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      10. Observation.text
      Definition

      A human-readable narrative that contains a summary of the resource, and may be used to represent the content of the resource to a human. The narrative need not encode all the structured data, but is required to contain sufficient detail to make it "clinically safe" for a human to just read the narrative. Resource definitions may define what content should be represented in the narrative to ensure clinical safety.

      ShortText summary of the resource, for human interpretation
      Comments

      Contained resources do not have narrative. Resources that are not contained SHOULD have a narrative. In some cases, a resource may only have text with little or no additional discrete data (as long as all minOccurs=1 elements are satisfied). This may be necessary for data from legacy systems where information is captured as a "text blob" or where text is additionally entered raw or narrated and encoded in formation is added later.

      Control0..1
      This element is affected by the following invariants: dom-1
      TypeNarrative
      Alternate Namesnarrative, html, xhtml, display
      12. Observation.contained
      Definition

      These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, and nor can they have their own independent transaction scope.

      ShortContained, inline Resources
      Comments

      This should never be done when the content can be identified properly, as once identification is lost, it is extremely difficult (and context dependent) to restore it again.

      Control0..*
      TypeResource
      Alternate Namesinline resources, anonymous resources, contained resources
      14. Observation.extension
      Definition

      May be used to represent additional information that is not part of the basic definition of the resource. In order 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 is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

      ShortAdditional Content defined by implementations
      Comments

      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.

      Control0..*
      TypeExtension
      Alternate Namesextensions, user content
      16. Observation.modifierExtension
      Definition

      May be used to represent additional information that is not part of the basic definition of the resource, and that modifies the understanding of the element that contains it. Usually modifier elements provide negation or qualification. In order 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 is allowed to 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.

      ShortExtensions that cannot be ignored
      Comments

      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.

      Control0..*
      TypeExtension
      Is Modifiertrue because No Modifier Reason provideed in previous versions of FHIR
      Alternate Namesextensions, user content
      18. Observation.identifier
      Definition

      A unique identifier assigned to this observation.

      ShortBusiness Identifier for observation
      NoteThis is a business identifier, not a resource identifier (see discussion)
      Control0..*
      TypeIdentifier
      Summarytrue
      Requirements

      Allows observations to be distinguished and referenced.

      20. Observation.basedOn
      Definition

      A plan, proposal or order that is fulfilled in whole or in part by this event.

      ShortFulfills plan, proposal or order
      Control0..*
      TypeReference(CarePlan, DeviceRequest, ImmunizationRecommendation, MedicationRequest, NutritionOrder, ProcedureRequest, ReferralRequest)
      Summarytrue
      Requirements

      Allows tracing of authorization for the event and tracking whether proposals/recommendations were acted upon.

      Alternate NamesFulfills
      22. Observation.status
      Definition

      The status of the result value.

      Shortregistered | preliminary | final | amended +
      Comments

      This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid.

      Control1..1
      BindingThe codes SHALL be taken from ObservationStatus
      (required to http://hl7.org/fhir/ValueSet/observation-status)

      Codes providing the status of an observation.

      Typecode
      Is Modifiertrue because No Modifier Reason provideed in previous versions of FHIR
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Summarytrue
      Requirements

      Need to track the status of individual results. Some results are finalized before the whole report is finalized.

      24. Observation.category
      Definition

      A code that classifies the general type of observation being made.

      ShortClassification of type of observation
      Comments

      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.

      Control0..*
      BindingThe codes SHOULD be taken from Observation Category Codes
      (preferred to http://hl7.org/fhir/ValueSet/observation-category)

      Codes for high level observation categories.

      TypeCodeableConcept
      Requirements

      Used for filtering what observations are retrieved and displayed.

      26. Observation.code
      Definition

      Describes what was observed. Sometimes this is called the observation "name".

      ShortType of observation (code / type)
      Control1..1
      BindingFor example codes, see LOINC Codes
      (example to http://hl7.org/fhir/ValueSet/observation-codes)

      Codes identifying names of simple observations.

      TypeCodeableConcept
      Summarytrue
      Requirements

      Knowing what kind of observation is being made is essential to understanding the observation.

      Alternate NamesName
      28. Observation.subject
      Definition

      The patient, or group of patients, location, or device whose characteristics (direct or indirect) are described by the observation and into whose record the observation is placed. Comments: Indirect characteristics may be those of a specimen, fetus, donor, other observer (for example a relative or EMT), or any observation made about the subject.

      ShortWho and/or what this is about
      Comments

      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.

      If the target of the observation is different than the subject, the general extension observation-focal-subject. may be used. However, the distinction between the patient's own value for an observation versus that of the fetus, or the donor or blood product unit, etc., are often specified in the observation code.

      Control1..1
      TypeReference(Group, Device, nl-core-location, nl-core-patient)
      Summarytrue
      Requirements

      Observations have no value if you don't know who or what they're about.

      30. Observation.context
      Definition

      The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made.

      ShortHealthcare event during which this observation is made
      Comments

      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 or episode but still be tied to the context of the encounter or episode (e.g. pre-admission lab tests).

      Control0..1
      TypeReference(nl-core-episodeofcare, HCIM Encounter, gp-Encounter)
      Requirements

      For some observations it may be important to know the link between an observation and a particular encounter.

      Alternate NamesEncounter
      32. Observation.effective[x]
      Definition

      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.

      ShortClinically relevant time/time-period for observation
      Comments

      At least a date should be present unless this observation is a historical report.

      Control0..1
      TypeChoice of: dateTime, Period
      [x] NoteSee Choice of Data Types for further information about how to use [x]
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Summarytrue
      Requirements

      Knowing when an observation was deemed true is important to its relevance as well as determining trends.

      Alternate NamesOccurrence
      34. Observation.issued
      Definition

      The date and time this observation was made available to providers, typically after the results have been reviewed and verified.

      ShortDate/Time this was made available
      Comments

      Updated when the result is updated.

      Control0..1
      Typeinstant
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Summarytrue
      36. Observation.performer
      Definition

      Who was responsible for asserting the observed value as "true".

      ShortWho is responsible for the observation
      Control0..*
      TypeReference(nl-core-organization, nl-core-patient, nl-core-practitioner, nl-core-relatedperson)
      Summarytrue
      Requirements

      May give a degree of confidence in the observation and also indicates where follow-up questions should be directed.

      38. Observation.performer.id
      Definition

      unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

      Shortxml:id (or equivalent in JSON)
      Control0..1
      Typestring
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      XML FormatIn the XML format, this property is represented as an attribute.
      40. Observation.performer.extension
      Definition

      An Extension

      ShortExtension
      Control0..*
      TypeExtension
      SlicingThis element introduces a set of slices on Observation.performer.extension. The slices are unordered and Open, and can be differentiated using the following discriminators:
      • value @ url
      • 42. Observation.performer.extension:practitionerRole
        Slice NamepractitionerRole
        Definition

        Optional Extension Element - found in all resources.

        ShortOptional Extensions Element
        Control0..1
        TypeExtension(PractitionerRole Reference) (Extension Type: Reference)
        44. Observation.performer.reference
        Definition

        A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources.

        ShortLiteral reference, Relative, internal or absolute URL
        Comments

        Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server.

        Control0..1
        This element is affected by the following invariants: ref-1
        Typestring
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        Summarytrue
        46. Observation.performer.identifier
        Definition

        An identifier for the other resource. This is used when there is no way to reference the other resource directly, either because the entity is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference.

        ShortLogical reference, when literal reference is not known
        Comments

        When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy.

        When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference

        Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it.

        NoteThis is a business identifier, not a resource identifier (see discussion)
        Control0..1
        TypeIdentifier
        Summarytrue
        48. Observation.performer.display
        Definition

        Plain text narrative that identifies the resource in addition to the resource reference.

        ShortText alternative for the resource
        Comments

        This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it.

        Control0..1
        Typestring
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        Summarytrue
        50. Observation.value[x]
        Definition

        The information determined as a result of making the observation, if the information has a simple value.

        ShortActual result
        Comments

        Normally, an observation will have either a single value or a set of related observations. A few observations (e.g. Apgar score) may have both a value and related observations (for an Apgar score, the observations from which the measure is derived). If a value is present, the datatype for this element should be determined by Observation.code. This element has a variable name depending on the type as follows: valueQuantity, valueCodeableConcept, valueString, valueBoolean, valueRange, valueRatio, valueSampledData, valueAttachment, valueTime, valueDateTime, or valuePeriod. (The name format is "'value' + the type name" with a capital on the first letter of the type).

        If the data element is usually coded or if the type associated with the Observation.value defines a coded value, use CodeableConcept instead of string datatype even if the value is uncoded text. A value set is bound to the ValueCodeableConcept element. For further discussion and examples see the notes section below.

        Control0..1
        This element is affected by the following invariants: obs-7
        TypeChoice of: Quantity, CodeableConcept, string, boolean, Range, Ratio, SampledData, Attachment, time, dateTime, Period
        [x] NoteSee Choice of Data Types for further information about how to use [x]
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        Summarytrue
        Requirements

        An observation exists to have a value, though it may not if it is in error, or if it represents a group of observations.

        52. Observation.dataAbsentReason
        Definition

        Provides a reason why the expected value in the element Observation.value[x] is missing.

        ShortWhy the result is missing
        Comments

        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.

        Control0..1
        This element is affected by the following invariants: obs-6
        BindingUnless not suitable, these codes SHALL be taken from Observation Value Absent Reason
        (extensible to http://hl7.org/fhir/ValueSet/observation-valueabsentreason)

        Codes specifying why the result (Observation.value[x]) is missing.

        TypeCodeableConcept
        Requirements

        For many results it is necessary to handle exceptional values in measurements.

        54. Observation.interpretation
        Definition

        The assessment made based on the result of the observation. Intended as a simple compact code often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. Otherwise known as abnormal flag.

        ShortHigh, low, normal, etc.
        Control0..1
        BindingUnless not suitable, these codes SHALL be taken from Observation Interpretation Codes
        (extensible to http://hl7.org/fhir/ValueSet/observation-interpretation)

        Codes identifying interpretations of observations.

        TypeCodeableConcept
        Requirements

        For some results, particularly numeric results, an interpretation is necessary to fully understand the significance of a result.

        Alternate NamesAbnormal Flag
        56. Observation.comment
        Definition

        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.

        ShortComments about result
        Control0..1
        Typestring
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        Requirements

        Need to be able to provide free text additional information.

        58. Observation.bodySite
        Definition

        Indicates the site on the subject's body where the observation was made (i.e. the target site).

        ShortObserved body part
        Comments

        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 body-site-instance.

        Control0..1
        BindingFor example codes, see SNOMED CT Body Structures
        (example to http://hl7.org/fhir/ValueSet/body-site)

        Codes describing anatomical locations. May include laterality.

        TypeCodeableConcept
        60. Observation.method
        Definition

        Indicates the mechanism used to perform the observation.

        ShortHow it was done
        Comments

        Only used if not implicit in code for Observation.code.

        Control0..1
        BindingFor example codes, see Observation Methods
        (example to http://hl7.org/fhir/ValueSet/observation-methods)

        Methods for simple observations.

        TypeCodeableConcept
        Requirements

        In some cases, method can impact results and is thus used for determining whether results can be compared or determining significance of results.

        62. Observation.specimen
        Definition

        The specimen that was used when this observation was made.

        ShortSpecimen used for this observation
        Comments

        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).

        Control0..1
        TypeReference(Specimen)
        64. Observation.device
        Definition

        The device used to generate the observation data.

        Short(Measurement) Device
        Comments

        An extension should be used if further typing of the device is needed. Devices used to support obtaining an observation can be represented using either an extension or through the Observation.related element.

        Control0..1
        TypeReference(Device, DeviceMetric)
        66. Observation.referenceRange
        Definition

        Guidance on how to interpret the value by comparison to a normal or recommended range.

        ShortProvides guide for interpretation
        Comments

        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 may 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.

        Control0..*
        TypeBackboneElement
        Requirements

        Knowing what values are considered "normal" can help evaluate the significance of a particular result. Need to be able to provide multiple reference ranges for different contexts.

        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() | (children().count() > id.count()))
        obs-3: Must have at least a low or a high or text (low.exists() or high.exists() or text.exists())
        68. Observation.referenceRange.id
        Definition

        unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

        Shortxml:id (or equivalent in JSON)
        Control0..1
        Typestring
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        XML FormatIn the XML format, this property is represented as an attribute.
        70. Observation.referenceRange.extension
        Definition

        May be used to represent additional information that is not part of the basic definition of the element. In order 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 is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

        ShortAdditional Content defined by implementations
        Comments

        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.

        Control0..*
        TypeExtension
        Alternate Namesextensions, user content
        72. Observation.referenceRange.modifierExtension
        Definition

        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 that contains it. Usually modifier elements provide negation or qualification. In order 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 is allowed to 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.

        ShortExtensions that cannot be ignored
        Comments

        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.

        Control0..*
        TypeExtension
        Is Modifiertrue because No Modifier Reason provideed in previous versions of FHIR
        Summarytrue
        Alternate Namesextensions, user content, modifiers
        74. Observation.referenceRange.low
        Definition

        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).

        ShortLow Range, if relevant
        Control0..1
        This element is affected by the following invariants: obs-3
        TypeQuantity(SimpleQuantity)
        76. Observation.referenceRange.high
        Definition

        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).

        ShortHigh Range, if relevant
        Control0..1
        This element is affected by the following invariants: obs-3
        TypeQuantity(SimpleQuantity)
        78. Observation.referenceRange.type
        Definition

        Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range.

        ShortReference range qualifier
        Comments

        This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed.

        Control0..1
        BindingUnless not suitable, these codes SHALL be taken from Observation Reference Range Meaning Codes
        (extensible to http://hl7.org/fhir/ValueSet/referencerange-meaning)

        Code for the meaning of a reference range.

        TypeCodeableConcept
        Requirements

        Need to be able to say what kind of reference range this is - normal, recommended, therapeutic, etc, - for proper interpretation.

        80. Observation.referenceRange.appliesTo
        Definition

        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.

        ShortReference range population
        Comments

        This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed.

        Control0..*
        BindingFor example codes, see Observation Reference Range Applies To Codes
        (example to http://hl7.org/fhir/ValueSet/referencerange-appliesto)

        Codes identifying the population the reference range applies to.

        TypeCodeableConcept
        Requirements

        Need to be able to identify the target population for proper interpretation.

        82. Observation.referenceRange.age
        Definition

        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.

        ShortApplicable age range, if relevant
        Control0..1
        TypeRange
        Requirements

        Some analytes vary greatly over age.

        84. Observation.referenceRange.text
        Definition

        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'.

        ShortText based reference range in an observation
        Control0..1
        Typestring
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        86. Observation.related
        Definition

        A reference to another resource (usually another Observation) whose relationship is defined by the relationship type code.

        ShortResource related to this observation
        Comments

        For a discussion on the ways Observations can assembled in groups together see Notes below.

        Control0..*
        TypeBackboneElement
        Summarytrue
        Requirements

        Normally, an observation will have either a value or a set of related observations. A few observations (e.g. Apgar score) may have both a value and a set of related observations or sometimes a QuestionnaireResponse from which the measure is derived.

        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() | (children().count() > id.count()))
        88. Observation.related.id
        Definition

        unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

        Shortxml:id (or equivalent in JSON)
        Control0..1
        Typestring
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        XML FormatIn the XML format, this property is represented as an attribute.
        90. Observation.related.extension
        Definition

        May be used to represent additional information that is not part of the basic definition of the element. In order 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 is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

        ShortAdditional Content defined by implementations
        Comments

        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.

        Control0..*
        TypeExtension
        Alternate Namesextensions, user content
        92. Observation.related.modifierExtension
        Definition

        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 that contains it. Usually modifier elements provide negation or qualification. In order 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 is allowed to 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.

        ShortExtensions that cannot be ignored
        Comments

        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.

        Control0..*
        TypeExtension
        Is Modifiertrue because No Modifier Reason provideed in previous versions of FHIR
        Summarytrue
        Alternate Namesextensions, user content, modifiers
        94. Observation.related.type
        Definition

        A code specifying the kind of relationship that exists with the target resource.

        Shorthas-member | derived-from | sequel-to | replaces | qualified-by | interfered-by
        Comments

        The "derived-from" type is the only logical choice when referencing the QuestionnaireAnswer resource.

        Control0..1
        BindingThe codes SHALL be taken from ObservationRelationshipType
        (required to http://hl7.org/fhir/ValueSet/observation-relationshiptypes)

        Codes specifying how two observations are related.

        Typecode
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        Requirements

        A relationship type SHOULD be provided.

        96. Observation.related.target
        Definition

        A reference to the observation or QuestionnaireResponse resource that is related to this observation.

        ShortResource that is related to this one
        Control1..1
        TypeReference(Observation, QuestionnaireResponse, Sequence)
        98. Observation.component
        Definition

        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.

        ShortComponent results
        Comments

        For a discussion on the ways Observations can be assembled in groups together see Notes below.

        Control0..*
        TypeBackboneElement
        Summarytrue
        Requirements

        Component observations share the same attributes in the Observation resource as the primary observation and are always treated a part of a single observation (they are not separable). However, the reference range for the primary observation value is not inherited by the component values and is required when appropriate for each component observation.

        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() | (children().count() > id.count()))
        100. Observation.component.id
        Definition

        unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

        Shortxml:id (or equivalent in JSON)
        Control0..1
        Typestring
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        XML FormatIn the XML format, this property is represented as an attribute.
        102. Observation.component.extension
        Definition

        May be used to represent additional information that is not part of the basic definition of the element. In order 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 is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

        ShortAdditional Content defined by implementations
        Comments

        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.

        Control0..*
        TypeExtension
        Alternate Namesextensions, user content
        104. Observation.component.modifierExtension
        Definition

        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 that contains it. Usually modifier elements provide negation or qualification. In order 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 is allowed to 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.

        ShortExtensions that cannot be ignored
        Comments

        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.

        Control0..*
        TypeExtension
        Is Modifiertrue because No Modifier Reason provideed in previous versions of FHIR
        Summarytrue
        Alternate Namesextensions, user content, modifiers
        106. Observation.component.code
        Definition

        Describes what was observed. Sometimes this is called the observation "code".

        ShortType of component observation (code / type)
        Control1..1
        BindingFor example codes, see LOINC Codes
        (example to http://hl7.org/fhir/ValueSet/observation-codes)

        Codes identifying names of simple observations.

        TypeCodeableConcept
        Summarytrue
        Requirements

        Knowing what kind of observation is being made is essential to understanding the observation.

        108. Observation.component.value[x]
        Definition

        The information determined as a result of making the observation, if the information has a simple value.

        ShortActual component result
        Comments

        Normally, an observation will have either a single value or a set of related observations. A few observations (e.g. Apgar score) may have both a value and related observations (for an Apgar score, the observations from which the measure is 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 boolean values use valueCodeableConcept and select codes from <http://hl7.org/fhir/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"). The element, Observation.value[x], has a variable name depending on the type as follows: valueQuantity, valueCodeableConcept, valueRatio, valueChoice, valuePeriod, valueSampleData, or valueString (the name format is "'value' + the type name" with a capital on the first letter of the type).

        Control0..1
        TypeChoice of: Quantity, CodeableConcept, string, Range, Ratio, SampledData, Attachment, time, dateTime, Period
        [x] NoteSee Choice of Data Types for further information about how to use [x]
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        Summarytrue
        Requirements

        An observation exists to have a value, though it may not if it is in error, or if it represents a group of observations.

        110. Observation.component.dataAbsentReason
        Definition

        Provides a reason why the expected value in the element Observation.value[x] is missing.

        ShortWhy the component result is missing
        Comments

        "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.

        Control0..1
        This element is affected by the following invariants: obs-6
        BindingUnless not suitable, these codes SHALL be taken from Observation Value Absent Reason
        (extensible to http://hl7.org/fhir/ValueSet/observation-valueabsentreason)

        Codes specifying why the result (Observation.value[x]) is missing.

        TypeCodeableConcept
        Requirements

        For many results it is necessary to handle exceptional values in measurements.

        112. Observation.component.interpretation
        Definition

        The assessment made based on the result of the observation. Intended as a simple compact code often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. Otherwise known as abnormal flag.

        ShortHigh, low, normal, etc.
        Comments

        The component interpretation applies only to the individual component value. For an overall interpretation all components together use thes Observation.interpretation element.

        Control0..1
        BindingUnless not suitable, these codes SHALL be taken from Observation Interpretation Codes
        (extensible to http://hl7.org/fhir/ValueSet/observation-interpretation)

        Codes identifying interpretations of observations.

        TypeCodeableConcept
        Requirements

        For some results, particularly numeric results, an interpretation is necessary to fully understand the significance of a result.

        Alternate NamesAbnormal Flag
        114. Observation.component.referenceRange
        Definition

        Guidance on how to interpret the value by comparison to a normal or recommended range.

        ShortProvides guide for interpretation of component result
        Comments

        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 may 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.

        Control0..*
        TypeSee ttp://hl7.org/fhir/StructureDefinition/Observation#Observation.referenceRange
        Requirements

        Knowing what values are considered "normal" can help evaluate the significance of a particular result. Need to be able to provide multiple reference ranges for different contexts.