Personal Health Device Implementation Guide
2.0.0-ballot - STU2 Ballot International flag

This page is part of the Personal Health Device FHIR IG (v2.0.0-ballot: STU 2 Ballot 1) based on FHIR (HL7® FHIR® Standard) v4.3.0. The current version which supersedes this version is 1.0.0. For a full list of available versions, see the Directory of published versions

Resource Profile: PhdCoincidentTimeStampObservation - Detailed Descriptions

Draft as of 2017-06-02

Definitions for the PhdCoincidentTimeStampObservation resource profile.

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

0. Observation
Definition

The PhdCoincidentTimeStampObservation reports the current time of the PHD sensor at the current time of the PHG.

Comments

Used to record the correction the PHG applied to the PHD measurement time stamps (if any) and to be able to recover the original time stamps reported by the PHD should that be needed.

2. Observation.extension
ShortExtension for the PHG
Control1..1
4. Observation.extension.extension
Control0..0
6. Observation.extension.url
ShortUrl indicating this is the gateway device extension
Fixed Valuehttp://hl7.org/fhir/StructureDefinition/observation-gatewayDevice
8. Observation.extension.value[x]
ShortReference to the Personal Health Gateway (PHG) Device
Control1..?
TypeReference
[x] NoteSeeChoice of Data Typesfor further information about how to use [x]
10. Observation.status
Definition

The status of the result value. Always 'final'

Comments

The value shall be set to 'final'

Fixed Valuefinal
12. Observation.code
14. Observation.code.coding
Control1..?
SlicingThis element introduces a set of slices on Observation.code.coding. The slices areUnordered and Open, and can be differentiated using the following discriminators:
  • value @ system
  • 16. Observation.code.coding:MDCType
    Slice NameMDCType
    ShortThe required MDC code for the type of time clock used by the PHD
    Comments

    PHDs use one of absolute time, base offset time, relative time, or high resolution relative time.

    Control1..1
    18. Observation.code.coding:MDCType.system
    Control1..?
    Fixed Valueurn:iso:std:iso:11073:10101
    20. Observation.code.coding:MDCType.code
    Comments

    The code for absolute time is 67975 with reference id MDC_ATTR_TIME_ABS, for base offset time is 68226 with reference id MDC_ATTR_TIME_BO, for relative time is 67983 with reference id MDC_ATTR_TIME_REL, and for high resolution relative time is 68072 with reference id MDC_ATTR_TIME_REL_HI_RES.

    Control1..?
    22. Observation.subject
    Control1..?
    24. Observation.subject.reference
    Control1..?
    26. Observation.effective[x]
    Definition

    The time of the PHG at the time the current time of the PHD is ascertained.

    ShortThe current time of the PHG at the current time of the PHD. Absent if PHD is better synchronized
    Comments

    This element is absent if the PHD has superior time synchronization relative to the PHG. Wnen this element is absent it indicates that the PHG reported the measurement time stamps of the PHD without modification.

    [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
    28. Observation.value[x]
    Definition

    The current time of the PHD. It will be either a valueDateTime if a wallclock time or a valueQuantity if a relative time or a dataAbsentReason if there is a time fault. The relative time is expressed in microseconds

    ShortThe current time of the PHD as a wallclock time (dateTime), relative time (Quantity), or if a time fault a dataAbsentReason
    TypeChoice of: Quantity, dateTime, boolean, string, SampledData, Period, Ratio, integer, time, Range, CodeableConcept
    [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    30. Observation.dataAbsentReason
    Definition

    In this profile this element indicates that the current time of the PHD for the measurements reported is not known and is unable to be obtained

    ShortPopulated when the PHD has a time fault
    Comments

    This situation arises when the PHD has a time fault, perhaps by battery change. The sensor device may have stored data with time stamps taken at a time when the clock was running but after the fault the original time line was not able to be recovered. Thus the current time line, if any, has an unknown relationship to the previous time line.

    32. Observation.dataAbsentReason.coding
    Control1..?
    SlicingThis element introduces a set of slices on Observation.dataAbsentReason.coding. The slices areUnordered and Open, and can be differentiated using the following discriminators:
    • value @ system
    • 34. Observation.dataAbsentReason.coding:FhirDefault
      Slice NameFhirDefault
      Control1..1
      36. Observation.dataAbsentReason.coding:FhirDefault.system
      Control1..?
      Fixed Valuehttp://terminology.hl7.org/CodeSystem/data-absent-reason
      38. Observation.dataAbsentReason.coding:FhirDefault.code
      Control1..?
      Fixed Valueunknown
      40. Observation.device
      Comments

      This field references the PHD Device

      Control1..?
      42. Observation.device.reference
      Definition

      Reference to the device resources that describes the sensor device taking the measurement.

      ShortReference to the device responsible for the measurement
      Comments

      This reference points to the Device resource containing information about the sensor device that took the measurement.

      Control1..?

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

      0. Observation
      Definition

      The PhdCoincidentTimeStampObservation reports the current time of the PHD sensor at the current time of the PHG.


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

      ShortMeasurements and simple assertions
      Comments

      Used to record the correction the PHG applied to the PHD measurement time stamps (if any) and to be able to recover the original time stamps reported by the PHD should that be needed.


      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.

      Control0..*
      Is Modifierfalse
      Must Supportfalse
      Summaryfalse
      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-3: If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource (contained.where(((id.exists() and ('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url)))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(uri) = '#').exists()).not()).trace('unmatched', id).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-5: If a resource is contained in another resource, it SHALL NOT have a security label (contained.meta.security.empty())
      dom-6: A resource should have narrative for robust management (text.`div`.exists())
      obs-6: dataAbsentReason SHALL only be present if Observation.value[x] is not present (dataAbsentReason.empty() or value.empty())
      obs-7: If Observation.code is the same as an Observation.component.code then the value element associated with the code SHALL NOT be present (value.empty() or component.code.where(coding.intersect(%resource.code.coding).exists()).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. Often, this is a reference to an implementation guide that defines the special rules along with other profiles etc.

      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. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of it's narrative along with other profiles, value sets, etc.

      Control0..1
      Typeuri
      Is Modifiertrue because This element is labeled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation
      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
      Must Supportfalse
      Summarytrue
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      4. Observation.extension
      Definition

      An Extension


      May be used to represent additional information that is not part of the basic definition of the resource. 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.

      ShortExtension for the PHGAdditional 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.

      Control10..1*
      TypeExtension
      Is Modifierfalse
      Must Supportfalse
      Summaryfalse
      Alternate Namesextensions, user content
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
      6. Observation.extension.extension
      Definition

      An Extension


      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.

      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..0*
      TypeExtension
      Is Modifierfalse
      Summaryfalse
      Alternate Namesextensions, user content
      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
      ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
      SlicingThis element introduces a set of slices on Observation.extension.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
      • value @ url
      • 8. Observation.extension.url
        Definition

        Source of the definition for the extension code - a logical name or a URL.

        ShortUrl indicating this is the gateway device extensionidentifies the meaning of the extension
        Comments

        The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

        Control1..1
        Typeuri
        Is Modifierfalse
        XML FormatIn the XML format, this property is represented as an attribute.
        Summaryfalse
        Fixed Valuehttp://hl7.org/fhir/StructureDefinition/observation-gatewayDevice
        10. Observation.extension.value[x]
        Definition

        Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

        ShortReference to the Personal Health Gateway (PHG) DeviceValue of extension
        Control10..1
        TypeReference, date, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, Identifier, RatioRange, Coding, SampledData, id, positiveInt, Distance, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, CodeableConcept, ParameterDefinition, dateTime, code, string, Contributor, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, TriggerDefinition, Quantity, uri, url, Annotation, ContactDetail, boolean, Expression, CodeableReference, Signature, unsignedInt, time
        [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
        Is Modifierfalse
        Summaryfalse
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        12. 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 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 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.

        Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

        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 Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
        Must Supportfalse
        Summaryfalse
        Requirements

        Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

        Alternate Namesextensions, user content
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
        14. Observation.status
        Definition

        The status of the result value. Always 'final'


        The status of the result value.

        Shortregistered | preliminary | final | amended +
        Comments

        The value shall be set to 'final'


        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|4.3.0
        (required to http://hl7.org/fhir/ValueSet/observation-status|4.3.0)

        Codes providing the status of an observation.

        Typecode
        Is Modifiertrue because This element is labeled as a modifier because it is a status element that contains status entered-in-error which means that the resource should not be treated as valid
        Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
        Must Supportfalse
        Summarytrue
        Requirements

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

        Fixed Valuefinal
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        16. Observation.code
        Definition

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

        ShortType of observation (code / type)
        Comments

        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.

        Control1..1
        BindingFor example codes, see LOINCCodeshttp://hl7.org/fhir/ValueSet/observation-codes
        (example to http://hl7.org/fhir/ValueSet/observation-codes)

        Codes identifying names of simple observations.

        TypeCodeableConcept
        Is Modifierfalse
        Must Supportfalse
        Summarytrue
        Requirements

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

        Alternate NamesName
        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        18. Observation.code.coding
        Definition

        A reference to a code defined by a terminology system.

        ShortCode defined by a terminology system
        Comments

        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.

        Control10..*
        TypeCoding
        Is Modifierfalse
        Summarytrue
        Requirements

        Allows for alternative encodings within a code system, and translations to other code systems.

        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
        SlicingThis element introduces a set of slices on Observation.code.coding. The slices areUnordered and Open, and can be differentiated using the following discriminators:
        • value @ system
        • 20. Observation.code.coding:MDCType
          Slice NameMDCType
          Definition

          A reference to a code defined by a terminology system.

          ShortThe required MDC code for the type of time clock used by the PHDCode defined by a terminology system
          Comments

          PHDs use one of absolute time, base offset time, relative time, or high resolution relative time.


          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.

          Control10..1*
          TypeCoding
          Is Modifierfalse
          Summarytrue
          Requirements

          Allows for alternative encodings within a code system, and translations to other code systems.

          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          22. Observation.code.coding:MDCType.system
          Definition

          The identification of the code system that defines the meaning of the symbol in the code.

          ShortIdentity of the terminology system
          Comments

          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.

          Control10..1
          Typeuri
          Is Modifierfalse
          Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
          Summarytrue
          Requirements

          Need to be unambiguous about the source of the definition of the symbol.

          Fixed Valueurn:iso:std:iso:11073:10101
          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          24. Observation.code.coding:MDCType.code
          Definition

          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).

          ShortSymbol in syntax defined by the system
          Comments

          The code for absolute time is 67975 with reference id MDC_ATTR_TIME_ABS, for base offset time is 68226 with reference id MDC_ATTR_TIME_BO, for relative time is 67983 with reference id MDC_ATTR_TIME_REL, and for high resolution relative time is 68072 with reference id MDC_ATTR_TIME_REL_HI_RES.

          Control10..1
          Typecode
          Is Modifierfalse
          Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
          Summarytrue
          Requirements

          Need to refer to a particular code in the system.

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

          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.

          ShortWho and/or what the observation 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.

          Control10..1
          TypeReference(Patient, Group, Device, Location, Organization, Procedure, Practitioner, Medication, Substance)
          Is Modifierfalse
          Must Supportfalse
          Summarytrue
          Requirements

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

          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          28. Observation.subject.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.

          Control10..1
          This element is affected by the following invariants: ref-1
          Typestring
          Is Modifierfalse
          Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
          Summarytrue
          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          30. Observation.effective[x]
          Definition

          The time of the PHG at the time the current time of the PHD is ascertained.


          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.

          ShortThe current time of the PHG at the current time of the PHD. Absent if PHD is better synchronizedClinically relevant time/time-period for observation
          Comments

          This element is absent if the PHD has superior time synchronization relative to the PHG. Wnen this element is absent it indicates that the PHG reported the measurement time stamps of the PHD without modification.


          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 datatype which allow the measurement to be tied to regular life events.

          Control0..1
          TypeChoice of: dateTime, Period, Timing, instant
          [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
          Is Modifierfalse
          Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
          Must Supportfalse
          Summarytrue
          Requirements

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

          Alternate NamesOccurrence
          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          32. Observation.value[x]
          Definition

          The current time of the PHD. It will be either a valueDateTime if a wallclock time or a valueQuantity if a relative time or a dataAbsentReason if there is a time fault. The relative time is expressed in microseconds


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

          ShortThe current time of the PHD as a wallclock time (dateTime), relative time (Quantity), or if a time fault a dataAbsentReasonActual result
          Comments

          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 below.

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

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

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

          In this profile this element indicates that the current time of the PHD for the measurements reported is not known and is unable to be obtained


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

          ShortPopulated when the PHD has a time faultWhy the result is missing
          Comments

          This situation arises when the PHD has a time fault, perhaps by battery change. The sensor device may have stored data with time stamps taken at a time when the clock was running but after the fault the original time line was not able to be recovered. Thus the current time line, if any, has an unknown relationship to the previous time line.


          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 DataAbsentReasonhttp://hl7.org/fhir/ValueSet/data-absent-reason
          (extensible to http://hl7.org/fhir/ValueSet/data-absent-reason)

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

          TypeCodeableConcept
          Is Modifierfalse
          Must Supportfalse
          Summaryfalse
          Requirements

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

          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          36. Observation.dataAbsentReason.coding
          Definition

          A reference to a code defined by a terminology system.

          ShortCode defined by a terminology system
          Comments

          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.

          Control10..*
          TypeCoding
          Is Modifierfalse
          Summarytrue
          Requirements

          Allows for alternative encodings within a code system, and translations to other code systems.

          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
          SlicingThis element introduces a set of slices on Observation.dataAbsentReason.coding. The slices areUnordered and Open, and can be differentiated using the following discriminators:
          • value @ system
          • 38. Observation.dataAbsentReason.coding:FhirDefault
            Slice NameFhirDefault
            Definition

            A reference to a code defined by a terminology system.

            ShortCode defined by a terminology system
            Comments

            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.

            Control10..1*
            TypeCoding
            Is Modifierfalse
            Summarytrue
            Requirements

            Allows for alternative encodings within a code system, and translations to other code systems.

            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            40. Observation.dataAbsentReason.coding:FhirDefault.system
            Definition

            The identification of the code system that defines the meaning of the symbol in the code.

            ShortIdentity of the terminology system
            Comments

            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.

            Control10..1
            Typeuri
            Is Modifierfalse
            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
            Summarytrue
            Requirements

            Need to be unambiguous about the source of the definition of the symbol.

            Fixed Valuehttp://terminology.hl7.org/CodeSystem/data-absent-reason
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            42. Observation.dataAbsentReason.coding:FhirDefault.code
            Definition

            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).

            ShortSymbol in syntax defined by the system
            Control10..1
            Typecode
            Is Modifierfalse
            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
            Summarytrue
            Requirements

            Need to refer to a particular code in the system.

            Fixed Valueunknown
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            44. Observation.device
            Definition

            The device used to generate the observation data.

            Short(Measurement) Device
            Comments

            This field references the PHD Device


            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.

            Control10..1
            TypeReference(Device, DeviceMetric)
            Is Modifierfalse
            Must Supportfalse
            Summaryfalse
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            46. Observation.device.reference
            Definition

            Reference to the device resources that describes the sensor device taking the measurement.


            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.

            ShortReference to the device responsible for the measurementLiteral reference, Relative, internal or absolute URL
            Comments

            This reference points to the Device resource containing information about the sensor device that took the measurement.


            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.

            Control10..1
            This element is affected by the following invariants: ref-1
            Typestring
            Is Modifierfalse
            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
            Summarytrue
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))

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

            0. Observation
            Definition

            The PhdCoincidentTimeStampObservation reports the current time of the PHD sensor at the current time of the PHG.

            ShortMeasurements and simple assertions
            Comments

            Used to record the correction the PHG applied to the PHD measurement time stamps (if any) and to be able to recover the original time stamps reported by the PHD should that be needed.

            Control0..*
            Is Modifierfalse
            Must Supportfalse
            Summaryfalse
            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-3: If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource (contained.where(((id.exists() and ('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url)))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(uri) = '#').exists()).not()).trace('unmatched', id).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-5: If a resource is contained in another resource, it SHALL NOT have a security label (contained.meta.security.empty())
            dom-6: A resource should have narrative for robust management (text.`div`.exists())
            obs-6: dataAbsentReason SHALL only be present if Observation.value[x] is not present (dataAbsentReason.empty() or value.empty())
            obs-7: If Observation.code is the same as an Observation.component.code then the value element associated with the code SHALL NOT be present (value.empty() or component.code.where(coding.intersect(%resource.code.coding).exists()).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
            Is Modifierfalse
            Must Supportfalse
            Summarytrue
            4. Observation.meta
            Definition

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

            ShortMetadata about the resource
            Control0..1
            TypeMeta
            Is Modifierfalse
            Must Supportfalse
            Summarytrue
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            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. Often, this is a reference to an implementation guide that defines the special rules along with other profiles etc.

            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. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of it's narrative along with other profiles, value sets, etc.

            Control0..1
            Typeuri
            Is Modifiertrue because This element is labeled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation
            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
            Must Supportfalse
            Summarytrue
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            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
            BindingThe codes SHOULD be taken from CommonLanguages
            (preferred to http://hl7.org/fhir/ValueSet/languages)

            IETF language tag

            Additional BindingsPurpose
            AllLanguagesMax Binding
            Typecode
            Is Modifierfalse
            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
            Must Supportfalse
            Summaryfalse
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            10. Observation.text
            Definition

            A human-readable narrative that contains a summary of the resource and can 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 information is added later.

            Control0..1
            TypeNarrative
            Is Modifierfalse
            Must Supportfalse
            Summaryfalse
            Alternate Namesnarrative, html, xhtml, display
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            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. Contained resources may have profiles and tags In their meta elements, but SHALL NOT have security labels.

            Control0..*
            TypeResource
            Is Modifierfalse
            Must Supportfalse
            Summaryfalse
            Alternate Namesinline resources, anonymous resources, contained resources
            Invariantsdom-r4b: Containing new R4B resources within R4 resources may cause interoperability issues if instances are shared with R4 systems (($this is Citation or $this is Evidence or $this is EvidenceReport or $this is EvidenceVariable or $this is MedicinalProductDefinition or $this is PackagedProductDefinition or $this is AdministrableProductDefinition or $this is Ingredient or $this is ClinicalUseDefinition or $this is RegulatedAuthorization or $this is SubstanceDefinition or $this is SubscriptionStatus or $this is SubscriptionTopic) implies (%resource is Citation or %resource is Evidence or %resource is EvidenceReport or %resource is EvidenceVariable or %resource is MedicinalProductDefinition or %resource is PackagedProductDefinition or %resource is AdministrableProductDefinition or %resource is Ingredient or %resource is ClinicalUseDefinition or %resource is RegulatedAuthorization or %resource is SubstanceDefinition or %resource is SubscriptionStatus or %resource is SubscriptionTopic))
            14. Observation.extension
            Definition

            An Extension

            ShortExtension for the PHG
            Control1..1
            TypeExtension
            Is Modifierfalse
            Must Supportfalse
            Summaryfalse
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
            16. Observation.extension.id
            Definition

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

            ShortUnique id for inter-element referencing
            Control0..1
            Typeid
            Is Modifierfalse
            XML FormatIn the XML format, this property is represented as an attribute.
            Summaryfalse
            18. Observation.extension.extension
            Definition

            An Extension

            ShortExtension
            Control0..0
            TypeExtension
            Is Modifierfalse
            Summaryfalse
            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
            ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
            SlicingThis element introduces a set of slices on Observation.extension.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
            • value @ url
            • 20. Observation.extension.url
              Definition

              Source of the definition for the extension code - a logical name or a URL.

              ShortUrl indicating this is the gateway device extension
              Comments

              The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension.

              Control1..1
              Typeuri
              Is Modifierfalse
              XML FormatIn the XML format, this property is represented as an attribute.
              Summaryfalse
              Fixed Valuehttp://hl7.org/fhir/StructureDefinition/observation-gatewayDevice
              22. Observation.extension.value[x]
              Definition

              Value of extension - must be one of a constrained set of the data types (see Extensibility for a list).

              ShortReference to the Personal Health Gateway (PHG) Device
              Control1..1
              TypeReference
              [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
              Is Modifierfalse
              Summaryfalse
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              24. 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 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 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.

              Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

              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 Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
              Must Supportfalse
              Summaryfalse
              Requirements

              Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

              Alternate Namesextensions, user content
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
              26. 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
              Is Modifierfalse
              Must Supportfalse
              Summarytrue
              Requirements

              Allows observations to be distinguished and referenced.

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

              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.

              ShortFulfills plan, proposal or order
              Control0..*
              TypeReference(CarePlan, DeviceRequest, ImmunizationRecommendation, MedicationRequest, NutritionOrder, ServiceRequest)
              Is Modifierfalse
              Must Supportfalse
              Summarytrue
              Requirements

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

              Alternate NamesFulfills
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              30. Observation.partOf
              Definition

              A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure.

              ShortPart of referenced event
              Comments

              To link an Observation to an Encounter use encounter. See the Notes below for guidance on referencing another Observation.

              Control0..*
              TypeReference(MedicationAdministration, MedicationDispense, MedicationStatement, Procedure, Immunization, ImagingStudy)
              Is Modifierfalse
              Must Supportfalse
              Summarytrue
              Alternate NamesContainer
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              32. Observation.status
              Definition

              The status of the result value. Always 'final'

              Shortregistered | preliminary | final | amended +
              Comments

              The value shall be set to 'final'

              Control1..1
              BindingThe codes SHALL be taken from ObservationStatus
              (required to http://hl7.org/fhir/ValueSet/observation-status|4.3.0)

              Codes providing the status of an observation.

              Typecode
              Is Modifiertrue because This element is labeled as a modifier because it is a status element that contains status entered-in-error which means that the resource should not be treated as valid
              Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
              Must Supportfalse
              Summarytrue
              Requirements

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

              Fixed Valuefinal
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              34. 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 ObservationCategoryCodes
              (preferred to http://hl7.org/fhir/ValueSet/observation-category)

              Codes for high level observation categories.

              TypeCodeableConcept
              Is Modifierfalse
              Must Supportfalse
              Summaryfalse
              Requirements

              Used for filtering what observations are retrieved and displayed.

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

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

              ShortType of observation (code / type)
              Comments

              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.

              Control1..1
              BindingFor example codes, see LOINCCodes
              (example to http://hl7.org/fhir/ValueSet/observation-codes)

              Codes identifying names of simple observations.

              TypeCodeableConcept
              Is Modifierfalse
              Must Supportfalse
              Summarytrue
              Requirements

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

              Alternate NamesName
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              38. Observation.code.id
              Definition

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

              ShortUnique id for inter-element referencing
              Control0..1
              Typeid
              Is Modifierfalse
              XML FormatIn the XML format, this property is represented as an attribute.
              Summaryfalse
              40. Observation.code.extension
              Definition

              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.

              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
              Is Modifierfalse
              Summaryfalse
              Alternate Namesextensions, user content
              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
              ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
              SlicingThis element introduces a set of slices on Observation.code.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
              • value @ url
              • 42. Observation.code.coding
                Definition

                A reference to a code defined by a terminology system.

                ShortCode defined by a terminology system
                Comments

                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.

                Control1..*
                TypeCoding
                Is Modifierfalse
                Summarytrue
                Requirements

                Allows for alternative encodings within a code system, and translations to other code systems.

                Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                SlicingThis element introduces a set of slices on Observation.code.coding. The slices areUnordered and Open, and can be differentiated using the following discriminators:
                • value @ system
                • 44. Observation.code.coding:MDCType
                  Slice NameMDCType
                  Definition

                  A reference to a code defined by a terminology system.

                  ShortThe required MDC code for the type of time clock used by the PHD
                  Comments

                  PHDs use one of absolute time, base offset time, relative time, or high resolution relative time.

                  Control1..1
                  TypeCoding
                  Is Modifierfalse
                  Summarytrue
                  Requirements

                  Allows for alternative encodings within a code system, and translations to other code systems.

                  Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                  46. Observation.code.coding:MDCType.id
                  Definition

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

                  ShortUnique id for inter-element referencing
                  Control0..1
                  Typeid
                  Is Modifierfalse
                  XML FormatIn the XML format, this property is represented as an attribute.
                  Summaryfalse
                  48. Observation.code.coding:MDCType.extension
                  Definition

                  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.

                  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
                  Is Modifierfalse
                  Summaryfalse
                  Alternate Namesextensions, user content
                  Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                  ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                  SlicingThis element introduces a set of slices on Observation.code.coding.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
                  • value @ url
                  • 50. Observation.code.coding:MDCType.system
                    Definition

                    The identification of the code system that defines the meaning of the symbol in the code.

                    ShortIdentity of the terminology system
                    Comments

                    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.

                    Control1..1
                    Typeuri
                    Is Modifierfalse
                    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                    Summarytrue
                    Requirements

                    Need to be unambiguous about the source of the definition of the symbol.

                    Fixed Valueurn:iso:std:iso:11073:10101
                    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                    52. Observation.code.coding:MDCType.version
                    Definition

                    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.

                    ShortVersion of the system - if relevant
                    Comments

                    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.

                    NoteThis is a business version Id, not a resource version Id (see discussion)
                    Control0..1
                    Typestring
                    Is Modifierfalse
                    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                    Summarytrue
                    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                    54. Observation.code.coding:MDCType.code
                    Definition

                    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).

                    ShortSymbol in syntax defined by the system
                    Comments

                    The code for absolute time is 67975 with reference id MDC_ATTR_TIME_ABS, for base offset time is 68226 with reference id MDC_ATTR_TIME_BO, for relative time is 67983 with reference id MDC_ATTR_TIME_REL, and for high resolution relative time is 68072 with reference id MDC_ATTR_TIME_REL_HI_RES.

                    Control1..1
                    Typecode
                    Is Modifierfalse
                    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                    Summarytrue
                    Requirements

                    Need to refer to a particular code in the system.

                    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                    56. Observation.code.coding:MDCType.display
                    Definition

                    A representation of the meaning of the code in the system, following the rules of the system.

                    ShortRepresentation defined by the system
                    Control0..1
                    Typestring
                    Is Modifierfalse
                    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                    Summarytrue
                    Requirements

                    Need to be able to carry a human-readable meaning of the code for readers that do not know the system.

                    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                    58. Observation.code.coding:MDCType.userSelected
                    Definition

                    Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).

                    ShortIf this coding was chosen directly by the user
                    Comments

                    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.

                    Control0..1
                    Typeboolean
                    Is Modifierfalse
                    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                    Summarytrue
                    Requirements

                    This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing.

                    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                    60. Observation.code.text
                    Definition

                    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.

                    ShortPlain text representation of the concept
                    Comments

                    Very often the text is the same as a displayName of one of the codings.

                    Control0..1
                    Typestring
                    Is Modifierfalse
                    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                    Summarytrue
                    Requirements

                    The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source.

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

                    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.

                    ShortWho and/or what the observation 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.

                    Control1..1
                    TypeReference(Patient, Group, Device, Location, Organization, Procedure, Practitioner, Medication, Substance)
                    Is Modifierfalse
                    Must Supportfalse
                    Summarytrue
                    Requirements

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

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

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

                    ShortUnique id for inter-element referencing
                    Control0..1
                    Typeid
                    Is Modifierfalse
                    XML FormatIn the XML format, this property is represented as an attribute.
                    Summaryfalse
                    66. Observation.subject.extension
                    Definition

                    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.

                    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
                    Is Modifierfalse
                    Summaryfalse
                    Alternate Namesextensions, user content
                    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                    ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                    SlicingThis element introduces a set of slices on Observation.subject.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
                    • value @ url
                    • 68. Observation.subject.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.

                      Control1..1
                      This element is affected by the following invariants: ref-1
                      Typestring
                      Is Modifierfalse
                      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                      Summarytrue
                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      70. Observation.subject.type
                      Definition

                      The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent.

                      The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources).

                      ShortType the reference refers to (e.g. "Patient")
                      Comments

                      This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified.

                      Control0..1
                      BindingUnless not suitable, these codes SHALL be taken from ResourceType
                      (extensible to http://hl7.org/fhir/ValueSet/resource-types)
                      Typeuri
                      Is Modifierfalse
                      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                      Summarytrue
                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      72. Observation.subject.identifier
                      Definition

                      An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents 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.

                      Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any).

                      NoteThis is a business identifier, not a resource identifier (see discussion)
                      Control0..1
                      TypeIdentifier
                      Is Modifierfalse
                      Summarytrue
                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      74. Observation.subject.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
                      Is Modifierfalse
                      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                      Summarytrue
                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      76. Observation.focus
                      Definition

                      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.

                      ShortWhat the observation is about, when it is not about the subject of record
                      Comments

                      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.

                      Control0..*
                      TypeReference(Resource)
                      Is Modifierfalse
                      Must Supportfalse
                      Summarytrue
                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      78. Observation.encounter
                      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 but still be tied to the context of the encounter (e.g. pre-admission laboratory tests).

                      Control0..1
                      TypeReference(Encounter)
                      Is Modifierfalse
                      Must Supportfalse
                      Summarytrue
                      Requirements

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

                      Alternate NamesContext
                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      80. Observation.effective[x]
                      Definition

                      The time of the PHG at the time the current time of the PHD is ascertained.

                      ShortThe current time of the PHG at the current time of the PHD. Absent if PHD is better synchronized
                      Comments

                      This element is absent if the PHD has superior time synchronization relative to the PHG. Wnen this element is absent it indicates that the PHG reported the measurement time stamps of the PHD without modification.

                      Control0..1
                      TypeChoice of: dateTime, Period, Timing, instant
                      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                      Is Modifierfalse
                      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                      Must Supportfalse
                      Summarytrue
                      Requirements

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

                      Alternate NamesOccurrence
                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      82. Observation.issued
                      Definition

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

                      ShortDate/Time this version was made available
                      Comments

                      For Observations that don’t require review and verification, it may be the same as the 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.

                      Control0..1
                      Typeinstant
                      Is Modifierfalse
                      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                      Must Supportfalse
                      Summarytrue
                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      84. Observation.performer
                      Definition

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

                      ShortWho is responsible for the observation
                      Control0..*
                      TypeReference(Practitioner, PractitionerRole, Organization, CareTeam, Patient, RelatedPerson)
                      Is Modifierfalse
                      Must Supportfalse
                      Summarytrue
                      Requirements

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

                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      86. Observation.value[x]
                      Definition

                      The current time of the PHD. It will be either a valueDateTime if a wallclock time or a valueQuantity if a relative time or a dataAbsentReason if there is a time fault. The relative time is expressed in microseconds

                      ShortThe current time of the PHD as a wallclock time (dateTime), relative time (Quantity), or if a time fault a dataAbsentReason
                      Comments

                      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 below.

                      Control0..1
                      This element is affected by the following invariants: obs-7
                      TypeChoice of: Quantity, dateTime
                      [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                      Is Modifierfalse
                      Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                      Must Supportfalse
                      Summarytrue
                      Requirements

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

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

                      In this profile this element indicates that the current time of the PHD for the measurements reported is not known and is unable to be obtained

                      ShortPopulated when the PHD has a time fault
                      Comments

                      This situation arises when the PHD has a time fault, perhaps by battery change. The sensor device may have stored data with time stamps taken at a time when the clock was running but after the fault the original time line was not able to be recovered. Thus the current time line, if any, has an unknown relationship to the previous time line.

                      Control0..1
                      This element is affected by the following invariants: obs-6
                      BindingUnless not suitable, these codes SHALL be taken from DataAbsentReason
                      (extensible to http://hl7.org/fhir/ValueSet/data-absent-reason)

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

                      TypeCodeableConcept
                      Is Modifierfalse
                      Must Supportfalse
                      Summaryfalse
                      Requirements

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

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

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

                      ShortUnique id for inter-element referencing
                      Control0..1
                      Typeid
                      Is Modifierfalse
                      XML FormatIn the XML format, this property is represented as an attribute.
                      Summaryfalse
                      92. Observation.dataAbsentReason.extension
                      Definition

                      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.

                      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
                      Is Modifierfalse
                      Summaryfalse
                      Alternate Namesextensions, user content
                      Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                      ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                      SlicingThis element introduces a set of slices on Observation.dataAbsentReason.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
                      • value @ url
                      • 94. Observation.dataAbsentReason.coding
                        Definition

                        A reference to a code defined by a terminology system.

                        ShortCode defined by a terminology system
                        Comments

                        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.

                        Control1..*
                        TypeCoding
                        Is Modifierfalse
                        Summarytrue
                        Requirements

                        Allows for alternative encodings within a code system, and translations to other code systems.

                        Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                        SlicingThis element introduces a set of slices on Observation.dataAbsentReason.coding. The slices areUnordered and Open, and can be differentiated using the following discriminators:
                        • value @ system
                        • 96. Observation.dataAbsentReason.coding:FhirDefault
                          Slice NameFhirDefault
                          Definition

                          A reference to a code defined by a terminology system.

                          ShortCode defined by a terminology system
                          Comments

                          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.

                          Control1..1
                          TypeCoding
                          Is Modifierfalse
                          Summarytrue
                          Requirements

                          Allows for alternative encodings within a code system, and translations to other code systems.

                          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                          98. Observation.dataAbsentReason.coding:FhirDefault.id
                          Definition

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

                          ShortUnique id for inter-element referencing
                          Control0..1
                          Typeid
                          Is Modifierfalse
                          XML FormatIn the XML format, this property is represented as an attribute.
                          Summaryfalse
                          100. Observation.dataAbsentReason.coding:FhirDefault.extension
                          Definition

                          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.

                          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
                          Is Modifierfalse
                          Summaryfalse
                          Alternate Namesextensions, user content
                          Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                          ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                          SlicingThis element introduces a set of slices on Observation.dataAbsentReason.coding.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
                          • value @ url
                          • 102. Observation.dataAbsentReason.coding:FhirDefault.system
                            Definition

                            The identification of the code system that defines the meaning of the symbol in the code.

                            ShortIdentity of the terminology system
                            Comments

                            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.

                            Control1..1
                            Typeuri
                            Is Modifierfalse
                            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                            Summarytrue
                            Requirements

                            Need to be unambiguous about the source of the definition of the symbol.

                            Fixed Valuehttp://terminology.hl7.org/CodeSystem/data-absent-reason
                            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                            104. Observation.dataAbsentReason.coding:FhirDefault.version
                            Definition

                            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.

                            ShortVersion of the system - if relevant
                            Comments

                            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.

                            NoteThis is a business version Id, not a resource version Id (see discussion)
                            Control0..1
                            Typestring
                            Is Modifierfalse
                            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                            Summarytrue
                            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                            106. Observation.dataAbsentReason.coding:FhirDefault.code
                            Definition

                            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).

                            ShortSymbol in syntax defined by the system
                            Control1..1
                            Typecode
                            Is Modifierfalse
                            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                            Summarytrue
                            Requirements

                            Need to refer to a particular code in the system.

                            Fixed Valueunknown
                            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                            108. Observation.dataAbsentReason.coding:FhirDefault.display
                            Definition

                            A representation of the meaning of the code in the system, following the rules of the system.

                            ShortRepresentation defined by the system
                            Control0..1
                            Typestring
                            Is Modifierfalse
                            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                            Summarytrue
                            Requirements

                            Need to be able to carry a human-readable meaning of the code for readers that do not know the system.

                            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                            110. Observation.dataAbsentReason.coding:FhirDefault.userSelected
                            Definition

                            Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).

                            ShortIf this coding was chosen directly by the user
                            Comments

                            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.

                            Control0..1
                            Typeboolean
                            Is Modifierfalse
                            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                            Summarytrue
                            Requirements

                            This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing.

                            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                            112. Observation.dataAbsentReason.text
                            Definition

                            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.

                            ShortPlain text representation of the concept
                            Comments

                            Very often the text is the same as a displayName of one of the codings.

                            Control0..1
                            Typestring
                            Is Modifierfalse
                            Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                            Summarytrue
                            Requirements

                            The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source.

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

                            A categorical assessment of an observation value. For example, high, low, normal.

                            ShortHigh, low, normal, etc.
                            Comments

                            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.

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

                            Codes identifying interpretations of observations.

                            TypeCodeableConcept
                            Is Modifierfalse
                            Must Supportfalse
                            Summaryfalse
                            Requirements

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

                            Alternate NamesAbnormal Flag
                            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                            116. Observation.note
                            Definition

                            Comments about the observation or the results.

                            ShortComments about the observation
                            Comments

                            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.

                            Control0..*
                            TypeAnnotation
                            Is Modifierfalse
                            Must Supportfalse
                            Summaryfalse
                            Requirements

                            Need to be able to provide free text additional information.

                            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                            118. 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 bodySite.

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

                            SNOMED CT Body site concepts

                            TypeCodeableConcept
                            Is Modifierfalse
                            Must Supportfalse
                            Summaryfalse
                            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                            120. 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 ObservationMethods
                            (example to http://hl7.org/fhir/ValueSet/observation-methods)

                            Methods for simple observations.

                            TypeCodeableConcept
                            Is Modifierfalse
                            Must Supportfalse
                            Summaryfalse
                            Requirements

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

                            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                            122. 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)
                            Is Modifierfalse
                            Must Supportfalse
                            Summaryfalse
                            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                            124. Observation.device
                            Definition

                            The device used to generate the observation data.

                            Short(Measurement) Device
                            Comments

                            This field references the PHD Device

                            Control1..1
                            TypeReference(Device, DeviceMetric)
                            Is Modifierfalse
                            Must Supportfalse
                            Summaryfalse
                            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                            126. Observation.device.id
                            Definition

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

                            ShortUnique id for inter-element referencing
                            Control0..1
                            Typeid
                            Is Modifierfalse
                            XML FormatIn the XML format, this property is represented as an attribute.
                            Summaryfalse
                            128. Observation.device.extension
                            Definition

                            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.

                            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
                            Is Modifierfalse
                            Summaryfalse
                            Alternate Namesextensions, user content
                            Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                            ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                            SlicingThis element introduces a set of slices on Observation.device.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
                            • value @ url
                            • 130. Observation.device.reference
                              Definition

                              Reference to the device resources that describes the sensor device taking the measurement.

                              ShortReference to the device responsible for the measurement
                              Comments

                              This reference points to the Device resource containing information about the sensor device that took the measurement.

                              Control1..1
                              This element is affected by the following invariants: ref-1
                              Typestring
                              Is Modifierfalse
                              Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                              Summarytrue
                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              132. Observation.device.type
                              Definition

                              The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent.

                              The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources).

                              ShortType the reference refers to (e.g. "Patient")
                              Comments

                              This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified.

                              Control0..1
                              BindingUnless not suitable, these codes SHALL be taken from ResourceType
                              (extensible to http://hl7.org/fhir/ValueSet/resource-types)
                              Typeuri
                              Is Modifierfalse
                              Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                              Summarytrue
                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              134. Observation.device.identifier
                              Definition

                              An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents 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.

                              Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any).

                              NoteThis is a business identifier, not a resource identifier (see discussion)
                              Control0..1
                              TypeIdentifier
                              Is Modifierfalse
                              Summarytrue
                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              136. Observation.device.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
                              Is Modifierfalse
                              Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                              Summarytrue
                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              138. Observation.referenceRange
                              Definition

                              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.

                              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 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.

                              Control0..*
                              TypeBackboneElement
                              Is Modifierfalse
                              Must Supportfalse
                              Summaryfalse
                              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 unless an empty Parameters resource (hasValue() or (children().count() > id.count()) or $this is Parameters)
                              obs-3: Must have at least a low or a high or text (low.exists() or high.exists() or text.exists())
                              140. 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.

                              ShortUnique id for inter-element referencing
                              Control0..1
                              Typestring
                              Is Modifierfalse
                              XML FormatIn the XML format, this property is represented as an attribute.
                              Summaryfalse
                              142. Observation.referenceRange.extension
                              Definition

                              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.

                              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
                              Is Modifierfalse
                              Summaryfalse
                              Alternate Namesextensions, user content
                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                              144. 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 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).

                              ShortExtensions that cannot be ignored even if unrecognized
                              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 Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
                              Summarytrue
                              Requirements

                              Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

                              Alternate Namesextensions, user content, modifiers
                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                              146. 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)
                              Is Modifierfalse
                              Must Supportfalse
                              Summaryfalse
                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              148. 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)
                              Is Modifierfalse
                              Must Supportfalse
                              Summaryfalse
                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              150. 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
                              BindingThe codes SHOULD be taken from ObservationReferenceRangeMeaningCodes
                              (preferred to http://hl7.org/fhir/ValueSet/referencerange-meaning)

                              Code for the meaning of a reference range.

                              TypeCodeableConcept
                              Is Modifierfalse
                              Must Supportfalse
                              Summaryfalse
                              Requirements

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

                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              152. 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. 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.

                              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 ObservationReferenceRangeAppliesToCodes
                              (example to http://hl7.org/fhir/ValueSet/referencerange-appliesto)

                              Codes identifying the population the reference range applies to.

                              TypeCodeableConcept
                              Is Modifierfalse
                              Must Supportfalse
                              Summaryfalse
                              Requirements

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

                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              154. 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
                              Is Modifierfalse
                              Must Supportfalse
                              Summaryfalse
                              Requirements

                              Some analytes vary greatly over age.

                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              156. 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
                              Is Modifierfalse
                              Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                              Must Supportfalse
                              Summaryfalse
                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              158. Observation.hasMember
                              Definition

                              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.

                              ShortRelated resource that belongs to the Observation group
                              Comments

                              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 below. Note that a system may calculate results from QuestionnaireResponse into a final score and represent the score as an Observation.

                              Control0..*
                              TypeReference(Observation, QuestionnaireResponse, MolecularSequence)
                              Is Modifierfalse
                              Must Supportfalse
                              Summarytrue
                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              160. Observation.derivedFrom
                              Definition

                              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.

                              ShortRelated measurements the observation is made from
                              Comments

                              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 below.

                              Control0..*
                              TypeReference(DocumentReference, ImagingStudy, Media, QuestionnaireResponse, Observation, MolecularSequence)
                              Is Modifierfalse
                              Must Supportfalse
                              Summarytrue
                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              162. 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
                              Is Modifierfalse
                              Must Supportfalse
                              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 unless an empty Parameters resource (hasValue() or (children().count() > id.count()) or $this is Parameters)
                              164. 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.

                              ShortUnique id for inter-element referencing
                              Control0..1
                              Typestring
                              Is Modifierfalse
                              XML FormatIn the XML format, this property is represented as an attribute.
                              Summaryfalse
                              166. Observation.component.extension
                              Definition

                              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.

                              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
                              Is Modifierfalse
                              Summaryfalse
                              Alternate Namesextensions, user content
                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                              168. 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 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).

                              ShortExtensions that cannot be ignored even if unrecognized
                              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 Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
                              Summarytrue
                              Requirements

                              Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

                              Alternate Namesextensions, user content, modifiers
                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
                              170. Observation.component.code
                              Definition

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

                              ShortType of component observation (code / type)
                              Comments

                              All code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation.

                              Control1..1
                              BindingFor example codes, see LOINCCodes
                              (example to http://hl7.org/fhir/ValueSet/observation-codes)

                              Codes identifying names of simple observations.

                              TypeCodeableConcept
                              Is Modifierfalse
                              Must Supportfalse
                              Summarytrue
                              Requirements

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

                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              172. 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

                              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 below.

                              Control0..1
                              TypeChoice of: Quantity, CodeableConcept, string, boolean, integer, Range, Ratio, SampledData, time, dateTime, Period
                              [x] NoteSeeChoice of Data Typesfor further information about how to use [x]
                              Is Modifierfalse
                              Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
                              Must Supportfalse
                              Summarytrue
                              Requirements

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

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

                              Provides a reason why the expected value in the element Observation.component.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 DataAbsentReason
                              (extensible to http://hl7.org/fhir/ValueSet/data-absent-reason)

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

                              TypeCodeableConcept
                              Is Modifierfalse
                              Must Supportfalse
                              Summaryfalse
                              Requirements

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

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

                              A categorical assessment of an observation value. For example, high, low, normal.

                              ShortHigh, low, normal, etc.
                              Comments

                              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.

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

                              Codes identifying interpretations of observations.

                              TypeCodeableConcept
                              Is Modifierfalse
                              Must Supportfalse
                              Summaryfalse
                              Requirements

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

                              Alternate NamesAbnormal Flag
                              Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
                              178. 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 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.

                              Control0..*
                              TypeSeettp://hl7.org/fhir/StructureDefinition/Observation#Observation.referenceRange
                              Is Modifierfalse
                              Must Supportfalse
                              Summaryfalse
                              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() or (children().count() > id.count()))