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Orders and Observations icon Work Group Maturity Level: 0Trial Use Use Context: Any

Definitions for the oxygensat Profile.

Observation
Element IdObservation
Definition

This profile defines how to represent Oxygen Saturation observations in FHIR using a standard LOINC code and UCUM units of measure.

Short DisplayFHIR Oxygen Saturation Profile
Cardinality0..*
Alternate NamesVital Signs, Measurement, Results, Tests
Comments

Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc.

Invariants
Inherited by this element
dom-2RuleIf the resource is contained in another resource, it SHALL NOT contain nested Resourcescontained.contained.empty()
vs-2RuleIf there is no component or hasMember element then either a value[x] or a data absent reason must be present.(component.empty() and hasMember.empty()) implies (dataAbsentReason.exists() or value.exists())
dom-3RuleIf the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resourcecontained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().ofType(canonical) | %resource.descendants().ofType(uri) | %resource.descendants().ofType(url))) or descendants().where(reference = '#').exists() or descendants().where(ofType(canonical) = '#').exists() or descendants().where(ofType(canonical) = '#').exists()).not()).trace('unmatched', id).empty()
dom-4RuleIf a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdatedcontained.meta.versionId.empty() and contained.meta.lastUpdated.empty()
dom-5RuleIf a resource is contained in another resource, it SHALL NOT have a security labelcontained.meta.security.empty()
dom-6GuidelineA resource should have narrative for robust managementtext.`div`.exists()
This is (only) a best practice guideline because:

When a resource has no narrative, only systems that fully understand the data can display the resource to a human safely. Including a human readable representation in the resource makes for a much more robust eco-system and cheaper handling of resources by intermediary systems. Some ecosystems restrict distribution of resources to only those systems that do fully understand the resources, and as a consequence implementers may believe that the narrative is superfluous. However experience shows that such eco-systems often open up to new participants over time.

obs-6RuledataAbsentReason SHALL only be present if Observation.value[x] is not presentdataAbsentReason.empty() or value.empty()
obs-7RuleIf Observation.component.code is the same as Observation.code, then Observation.value SHALL NOT be present (the Observation.component.value[x] holds the value).value.empty() or component.code.where(coding.intersect(%resource.code.coding).exists()).empty()
obs-8RulebodyStructure SHALL only be present if Observation.bodySite is not presentbodySite.exists() implies bodyStructure.empty()
Observation.id
Element IdObservation.id
Definition

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

Short DisplayLogical id of this artifact
Cardinality0..1
Typeid
Comments

Within the context of the FHIR RESTful interactions, the resource has an id except for cases like the create and conditional update. Otherwise, the use of the resouce id depends on the given use case.

Observation.meta
Element IdObservation.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.

Short DisplayMetadata about the resource
Cardinality0..1
TypeMeta
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.implicitRules
Element IdObservation.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.

Short DisplayA set of rules under which this content was created
Cardinality0..1
Typeuri
Is Modifiertrue (Reason: This element is labeled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies its meaning or interpretation)
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 its narrative along with other profiles, value sets, etc.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.language
Element IdObservation.language
Definition

The base language in which the resource is written.

Short DisplayLanguage of the resource content
Cardinality0..1
Terminology BindingIETF language tag for a human language
The codes SHALL be taken from All Languages
Typecode
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).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.text
Element IdObservation.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.

Short DisplayText summary of the resource, for human interpretation
Cardinality0..1 This element is affected by the following invariants: dom-6
TypeNarrative
Alternate Namesnarrative, html, xhtml, display
Comments

Contained resources do not have a 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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.contained
Element IdObservation.contained
Definition

These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, nor can they have their own independent transaction scope. This is allowed to be a Parameters resource if and only if it is referenced by a resource that provides context/meaning.

Short DisplayContained, inline Resources
Cardinality0..* This element is affected by the following invariants: dom-2, dom-4, dom-3, dom-5
TypeResource
Alternate Namesinline resources, anonymous resources, contained 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.

Observation.extension
Element IdObservation.extension
Definition

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 managable, 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.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.modifierExtension
Element IdObservation.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 managable, 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).

Short DisplayExtensions that cannot be ignored
Cardinality0..*
TypeExtension
Is Modifiertrue (Reason: Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them)
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
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.identifier
Element IdObservation.identifier
Definition

A unique identifier assigned to this observation.

Short DisplayBusiness Identifier for observation
Cardinality0..*
TypeIdentifier
Requirements

Allows observations to be distinguished and referenced.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.instantiates[x]
Element IdObservation.instantiates[x]
Definition

The reference to a FHIR ObservationDefinition resource that provides the definition that is adhered to in whole or in part by this Observation instance.

Short DisplayInstantiates FHIR ObservationDefinition
Cardinality0..1
TypeChoice of: canonical(ObservationDefinition), Reference(ObservationDefinition)
[x] NoteSee Choice of Datatypes for further information about how to use [x]
Comments

ObservationDefinition can be referenced by its canonical url using instantiatesCanonical, or by a name or an identifier using the appropriate sub-elements of instantiatesReference.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.basedOn
Element IdObservation.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.

Short DisplayFulfills plan, proposal or order
Cardinality0..*
TypeReference(CarePlan)
Requirements

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

Alternate NamesFulfills
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.triggeredBy
Element IdObservation.triggeredBy
Definition

Identifies the observation(s) that triggered the performance of this observation.

Short DisplayTriggering observation(s)
Cardinality0..*
TypeBackboneElement
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.triggeredBy.id
Element IdObservation.triggeredBy.id
Definition

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

Short DisplayUnique id for inter-element referencing
Cardinality0..1 This element is affected by the following invariants: ele-1
Typestring
Observation.triggeredBy.extension
Element IdObservation.triggeredBy.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 managable, 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.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.triggeredBy.modifierExtension
Element IdObservation.triggeredBy.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 managable, 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).

Short DisplayExtensions that cannot be ignored even if unrecognized
Cardinality0..*
TypeExtension
Is Modifiertrue (Reason: Modifier extensions are expected to modify the meaning or interpretation of the element that contains them)
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
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.triggeredBy.observation
Element IdObservation.triggeredBy.observation
Definition

Reference to the triggering observation.

Short DisplayTriggering observation
Cardinality1..1
TypeReference(Observation)
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.triggeredBy.type
Element IdObservation.triggeredBy.type
Definition

The type of trigger. Reflex | Repeat | Re-run.

Short Displayreflex | repeat | re-run
Cardinality1..1
Terminology BindingThe type of TriggeredBy Observation.
The codes SHALL be taken from triggered Bytype
Typecode
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.triggeredBy.reason
Element IdObservation.triggeredBy.reason
Definition

Provides the reason why this observation was performed as a result of the observation(s) referenced.

Short DisplayReason that the observation was triggered
Cardinality0..1
Typestring
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.partOf
Element IdObservation.partOf
Definition

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

Short DisplayPart of referenced event
Cardinality0..*
TypeReference(MedicationAdministration)
Alternate NamesContainer
Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.status
Element IdObservation.status
Definition

The status of the result value.

Short Displayregistered | preliminary | final | amended +
Cardinality1..1
Terminology Bindingnull
The codes SHALL be taken from Observation Status
Typecode
Is Modifiertrue (Reason: 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)
Must Supporttrue
Requirements

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

Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.category
Element IdObservation.category
Definition

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

Short DisplayClassification of type of observation
Cardinality1..*
Terminology BindingCodes for high level observation categories.
The codes SHOULD be taken from Observation Category Codes
TypeCodeableConcept
Must Supporttrue
Requirements

Used for filtering what observations are retrieved and displayed.

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:coding.code, value:coding.system
Observation.category(VSCat)
Element IdObservation.category:VSCat
Definition

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

Short DisplayClassification of type of observation
Cardinality1..1
Terminology BindingCodes for high level observation categories.
The codes SHOULD be taken from Observation Category Codes
TypeCodeableConcept
Must Supporttrue
Requirements

Used for filtering what observations are retrieved and displayed.

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.category.id
Element IdObservation.category:VSCat.id
Definition

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

Short DisplayUnique id for inter-element referencing
Cardinality0..1 This element is affected by the following invariants: ele-1
Typeid
Observation.category.extension
Element IdObservation.category:VSCat.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 managable, 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.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
Observation.category.coding
Element IdObservation.category:VSCat.coding
Definition

A reference to a code defined by a terminology system.

Short DisplayCode defined by a terminology system
Cardinality1..*
TypeCoding
Must Supporttrue
Requirements

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

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.category.coding.id
Element IdObservation.category:VSCat.coding.id
Definition

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

Short DisplayUnique id for inter-element referencing
Cardinality0..1 This element is affected by the following invariants: ele-1
Typeid
Observation.category.coding.extension
Element IdObservation.category:VSCat.coding.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 managable, 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.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
Observation.category.coding.system
Element IdObservation.category:VSCat.coding.system
Definition

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

Short DisplayIdentity of the terminology system
Cardinality1..1
Typeuri
Must Supporttrue
Requirements

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

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 be an absolute reference to some definition that establishes the system clearly and unambiguously.

Fixed Valuehttp://terminology.hl7.org/CodeSystem/observation-category
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.category.coding.version
Element IdObservation.category:VSCat.coding.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.

Short DisplayVersion of the system - if relevant
Cardinality0..1
Typestring
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.category.coding.code
Element IdObservation.category:VSCat.coding.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).

Short DisplaySymbol in syntax defined by the system
Cardinality1..1 This element is affected by the following invariants: cod-1
Typecode
Must Supporttrue
Requirements

Need to refer to a particular code in the system.

Fixed Valuevital-signs
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.category.coding.display
Element IdObservation.category:VSCat.coding.display
Definition

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

Short DisplayRepresentation defined by the system
Cardinality0..1 This element is affected by the following invariants: cod-1
Typestring
Requirements

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.category.coding.userSelected
Element IdObservation.category:VSCat.coding.userSelected
Definition

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

Short DisplayIf this coding was chosen directly by the user
Cardinality0..1
Typeboolean
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.

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.category.text
Element IdObservation.category:VSCat.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.

Short DisplayPlain text representation of the concept
Cardinality0..1
Typestring
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.

Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.code
Element IdObservation.code
Definition

Oxygen Saturation.

Short DisplayOxygen Saturation
Cardinality1..1 This element is affected by the following invariants: obs-7
Terminology BindingThis identifies the vital sign result type. Original source C-CDA R1.1 , HITSP Vital Sign Result Type.
The codes SHALL be taken from Vital Signs; other codes may be used where these codes are not suitable
TypeCodeableConcept
Must Supporttrue
Requirements
  1. SHALL contain exactly one [1..1] code, where the @code SHOULD be selected from ValueSet HITSP Vital Sign Result Type 2.16.840.1.113883.3.88.12.80.62 DYNAMIC (CONF:7301).
Alternate NamesName, Test
Comments

additional codes that translate or map to this code are allowed. For example a more granular LOINC code or code that is used locally in a system.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.code.id
Element IdObservation.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.

Short DisplayUnique id for inter-element referencing
Cardinality0..1 This element is affected by the following invariants: ele-1
Typeid
Observation.code.extension
Element IdObservation.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 managable, 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.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
Observation.code.coding
Element IdObservation.code.coding
Definition

A reference to a code defined by a terminology system.

Short DisplayCode defined by a terminology system
Cardinality1..*
TypeCoding
Requirements

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

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:code, value:system
Observation.code.coding(OxygenSatCode)
Element IdObservation.code.coding:OxygenSatCode
Definition

A reference to a code defined by a terminology system.

Short DisplayCode defined by a terminology system
Cardinality1..1
TypeCoding
Requirements

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

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.code.coding.id
Element IdObservation.code.coding:OxygenSatCode.id
Definition

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

Short DisplayUnique id for inter-element referencing
Cardinality0..1 This element is affected by the following invariants: ele-1
Typeid
Observation.code.coding.extension
Element IdObservation.code.coding:OxygenSatCode.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 managable, 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.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
Observation.code.coding.system
Element IdObservation.code.coding:OxygenSatCode.system
Definition

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

Short DisplayIdentity of the terminology system
Cardinality1..1
Typeuri
Requirements

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

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 be an absolute reference to some definition that establishes the system clearly and unambiguously.

Fixed Valuehttp://loinc.org
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.code.coding.version
Element IdObservation.code.coding:OxygenSatCode.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.

Short DisplayVersion of the system - if relevant
Cardinality0..1
Typestring
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.code.coding.code
Element IdObservation.code.coding:OxygenSatCode.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).

Short DisplaySymbol in syntax defined by the system
Cardinality1..1 This element is affected by the following invariants: cod-1
Typecode
Requirements

Need to refer to a particular code in the system.

Fixed Value2708-6
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.code.coding.display
Element IdObservation.code.coding:OxygenSatCode.display
Definition

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

Short DisplayRepresentation defined by the system
Cardinality0..1 This element is affected by the following invariants: cod-1
Typestring
Requirements

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.code.coding.userSelected
Element IdObservation.code.coding:OxygenSatCode.userSelected
Definition

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

Short DisplayIf this coding was chosen directly by the user
Cardinality0..1
Typeboolean
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.

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.code.text
Element IdObservation.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.

Short DisplayPlain text representation of the concept
Cardinality0..1
Typestring
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.

Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.subject
Element IdObservation.subject
Definition

The patient, or group of patients, location, device, organization, procedure or practitioner this observation is about and into whose or what 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.

Short DisplayWho and/or what the observation is about
Cardinality1..1
TypeReference(Patient)
Must Supporttrue
Requirements

Observations have no value if you don't know who or what they're 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. The subject of an Observation may in some cases be a procedure. This supports the regulatory inspection use case where observations are captured during inspections of a procedure that is being performed (independent of any particular patient or whether patient related at all).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.focus
Element IdObservation.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.

Short DisplayWhat the observation is about, when it is not about the subject of record
Cardinality0..*
TypeReference(Resource)
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 http://hl7.org/fhir/StructureDefinition/observation-focusCode.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.encounter
Element IdObservation.encounter
Definition

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

Short DisplayHealthcare event during which this observation is made
Cardinality0..1
TypeReference(Encounter)
Requirements

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

Alternate NamesContext
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).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.effective[x]
Element IdObservation.effective[x]
Definition

Often just a dateTime for Vital Signs.

Short DisplayOften just a dateTime for Vital Signs
Cardinality1..1 This element is affected by the following invariants: vs-1
TypeChoice of: dateTime, Period
[x] NoteSee Choice of Datatypes for further information about how to use [x]
Must Supporttrue
Requirements

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

Alternate NamesOccurrence
Comments

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
vs-1Ruleif Observation.effective[x] is dateTime and has a value then that value shall be precise to the day($this as dateTime).toString().length() >= 8
Observation.issued
Element IdObservation.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.

Short DisplayDate/Time this version was made available
Cardinality0..1
Typeinstant
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.performer
Element IdObservation.performer
Definition

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

Short DisplayWho is responsible for the observation
Cardinality0..*
TypeReference(Practitioner)
Requirements

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.value[x]
Element IdObservation.value[x]
Definition

Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept.

Short DisplayVital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept.
Cardinality0..1 This element is affected by the following invariants: obs-7, obs-6, vs-2
TypeQuantity
[x] NoteSee Choice of Datatypes for further information about how to use [x]
Must Supporttrue
Requirements
  1. SHALL contain exactly one [1..1] value with @xsi:type="PQ" (CONF:7305).
Comments
  • An observation may have:
    1. a single value here
    2. both a value and a set of related or component values
    3. only a set of related or component values.
  • If a value is present, the datatype for this element should be determined by the code.
  • 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 code defines a coded value.
  • Attachment is used if the observation result value is a binary file such as an image. If the observation result value is derived from the binary file (for example 'X' detected and here is the the proof in this image), the binary file may be directly represented using DocumentReference and referenced by derivedFrom.
  • The usage of valueReference is restricted to the MolecularSequence resource when used as a definitional resource, not as a patient-specific finding. .
  • For additional guidance, see the Notes section below.
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Closed
  • discriminators: type:$this
Observation.value[x](valueQuantity)
Element IdObservation.value[x]:valueQuantity
Definition

Vital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept.

Short DisplayVital Signs value are recorded using the Quantity data type. For supporting observations such as Cuff size could use other datatypes such as CodeableConcept.
Cardinality0..1 This element is affected by the following invariants: obs-7, obs-6, vs-2
TypeQuantity
[x] NoteSee Choice of Datatypes for further information about how to use [x]
Must Supporttrue
Requirements
  1. SHALL contain exactly one [1..1] value with @xsi:type="PQ" (CONF:7305).
Comments
  • An observation may have:
    1. a single value here
    2. both a value and a set of related or component values
    3. only a set of related or component values.
  • If a value is present, the datatype for this element should be determined by the code.
  • 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 code defines a coded value.
  • Attachment is used if the observation result value is a binary file such as an image. If the observation result value is derived from the binary file (for example 'X' detected and here is the the proof in this image), the binary file may be directly represented using DocumentReference and referenced by derivedFrom.
  • The usage of valueReference is restricted to the MolecularSequence resource when used as a definitional resource, not as a patient-specific finding. .
  • For additional guidance, see the Notes section below.
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.value[x].id
Element IdObservation.value[x]:valueQuantity.id
Definition

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

Short DisplayUnique id for inter-element referencing
Cardinality0..1 This element is affected by the following invariants: ele-1
Typeid
Observation.value[x].extension
Element IdObservation.value[x]:valueQuantity.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 managable, 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.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: value:url
Observation.value[x].value
Element IdObservation.value[x]:valueQuantity.value
Definition

The value of the measured amount. The value includes an implicit precision in the presentation of the value.

Short DisplayNumerical value (with implicit precision)
Cardinality1..1
Typedecimal
Must Supporttrue
Requirements

Precision is handled implicitly in almost all cases of measurement.

Comments

The implicit precision in the value should always be honored. Monetary values have their own rules for handling precision (refer to standard accounting text books).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.value[x].comparator
Element IdObservation.value[x]:valueQuantity.comparator
Definition

How the value should be understood and represented - whether the actual value is greater or less than the stated value due to measurement issues; e.g. if the comparator is "<" , then the real value is < stated value.

Short Display< | <= | >= | > | ad - how to understand the value
Cardinality0..1
Terminology BindingHow the Quantity should be understood and represented.
The codes SHALL be taken from QuantityComparator
Typecode
Is Modifiertrue (Reason: This is labeled as "Is Modifier" because the comparator modifies the interpretation of the value significantly. If there is no comparator, then there is no modification of the value)
Requirements

Need a framework for handling measures where the value is <5ug/L or >400mg/L due to the limitations of measuring methodology.

Meaning if MissingIf there is no comparator, then there is no modification of the value
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.value[x].unit
Element IdObservation.value[x]:valueQuantity.unit
Definition

A human-readable form of the unit.

Short DisplayUnit representation
Cardinality1..1
Typestring
Must Supporttrue
Requirements

There are many representations for units of measure and in many contexts, particular representations are fixed and required. I.e. mcg for micrograms.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.value[x].system
Element IdObservation.value[x]:valueQuantity.system
Definition

The identification of the system that provides the coded form of the unit.

Short DisplaySystem that defines coded unit form
Cardinality1..1 This element is affected by the following invariants: qty-3
Typeuri
Must Supporttrue
Requirements

Need to know the system that defines the coded form of the unit.

Fixed Valuehttp://unitsofmeasure.org
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.value[x].code
Element IdObservation.value[x]:valueQuantity.code
Definition

Coded responses from the common UCUM units for vital signs value set.

Short DisplayCoded responses from the common UCUM units for vital signs value set.
Cardinality1..1 This element is affected by the following invariants: qty-3
Typecode
Must Supporttrue
Requirements

Need a computable form of the unit that is fixed across all forms. UCUM provides this for quantities, but SNOMED CT provides many units of interest.

Comments

The preferred system is UCUM, but SNOMED CT can also be used (for customary units) or ISO 4217 for currency. The context of use may additionally require a code from a particular system.

Fixed Value%
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.dataAbsentReason
Element IdObservation.dataAbsentReason
Definition

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

Short DisplayWhy the result value is missing
Cardinality0..1 This element is affected by the following invariants: obs-6, vs-2
Terminology BindingCodes specifying why the result (`Observation.value[x]`) is missing.
The codes SHALL be taken from Data Absent Reason; other codes may be used where these codes are not suitable
TypeCodeableConcept
Must Supporttrue
Requirements

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

Comments

Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory".

The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.interpretation
Element IdObservation.interpretation
Definition

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

Short DisplayHigh, low, normal, etc
Cardinality0..*
Terminology BindingCodes identifying interpretations of observations.
The codes SHALL be taken from Observation Interpretation Codes; other codes may be used where these codes are not suitable
TypeCodeableConcept
Requirements

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

Alternate NamesAbnormal Flag
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.note
Element IdObservation.note
Definition

Comments about the observation or the results.

Short DisplayComments about the observation
Cardinality0..*
TypeAnnotation
Requirements

Need to be able to provide free text additional information.

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.bodySite
Element IdObservation.bodySite
Definition

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

Short DisplayObserved body part
Cardinality0..1 This element is affected by the following invariants: obs-8
Terminology BindingSNOMED CT Body site concepts
For example codes, see SNOMED CT Body Structures
TypeCodeableConcept
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.bodyStructure
Element IdObservation.bodyStructure
Definition

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

Short DisplayObserved body structure
Cardinality0..1 This element is affected by the following invariants: obs-8
TypeReference(BodyStructure)
Comments

Only used if not implicit in code found in Observation.code or bodySite is used. In many systems, this may be represented as a related observation instead of an inline component.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.method
Element IdObservation.method
Definition

Indicates the mechanism used to perform the observation.

Short DisplayHow it was done
Cardinality0..1
Terminology BindingMethods for simple observations.
For example codes, see Observation Methods
TypeCodeableConcept
Requirements

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

Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.specimen
Element IdObservation.specimen
Definition

The specimen that was used when this observation was made.

Short DisplaySpecimen used for this observation
Cardinality0..1
TypeReference(Specimen)
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).

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
obs-9RuleIf Observation.specimen is a reference to Group, the group can only have specimens(reference.resolve().exists() and reference.resolve() is Group) implies reference.resolve().member.entity.resolve().all($this is Specimen)
Observation.device
Element IdObservation.device
Definition

A reference to the device that generates the measurements or the device settings for the device.

Short DisplayA reference to the device that generates the measurements or the device settings for the device
Cardinality0..1
TypeReference(Device)
Comments

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange
Element IdObservation.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.

Short DisplayProvides guide for interpretation
Cardinality0..*
TypeBackboneElement
Requirements

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

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
obs-3RuleMust have at least a low or a high or textlow.exists() or high.exists() or text.exists()
Observation.referenceRange.id
Element IdObservation.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.

Short DisplayUnique id for inter-element referencing
Cardinality0..1 This element is affected by the following invariants: ele-1
Typestring
Observation.referenceRange.extension
Element IdObservation.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 managable, 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.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange.modifierExtension
Element IdObservation.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 managable, 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).

Short DisplayExtensions that cannot be ignored even if unrecognized
Cardinality0..*
TypeExtension
Is Modifiertrue (Reason: Modifier extensions are expected to modify the meaning or interpretation of the element that contains them)
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
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange.low
Element IdObservation.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).

Short DisplayLow Range, if relevant
Cardinality0..1 This element is affected by the following invariants: obs-3
TypeQuantity(SimpleQuantity)
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange.high
Element IdObservation.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).

Short DisplayHigh Range, if relevant
Cardinality0..1 This element is affected by the following invariants: obs-3
TypeQuantity(SimpleQuantity)
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange.normalValue
Element IdObservation.referenceRange.normalValue
Definition

The value of the normal value of the reference range.

Short DisplayNormal value, if relevant
Cardinality0..1
Terminology BindingCodes identifying the normal value of the observation.
The codes SHALL be taken from Observation Reference Range Normal Value Codes; other codes may be used where these codes are not suitable
TypeCodeableConcept
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange.type
Element IdObservation.referenceRange.type
Definition

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

Short DisplayReference range qualifier
Cardinality0..1
Terminology BindingCode for the meaning of a reference range.
The codes SHOULD be taken from Observation Reference Range Meaning Codes
TypeCodeableConcept
Requirements

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

Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange.appliesTo
Element IdObservation.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.

Short DisplayReference range population
Cardinality0..*
Terminology BindingCodes identifying the population the reference range applies to.
For example codes, see Observation Reference Range Applies To Codes
TypeCodeableConcept
Requirements

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

Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange.age
Element IdObservation.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.

Short DisplayApplicable age range, if relevant
Cardinality0..1
TypeRange
Requirements

Some analytes vary greatly over age.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.referenceRange.text
Element IdObservation.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".

Short DisplayText based reference range in an observation
Cardinality0..1 This element is affected by the following invariants: obs-3
Typemarkdown
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.hasMember
Element IdObservation.hasMember
Definition

Used when reporting vital signs panel components.

Short DisplayUsed when reporting vital signs panel components
Cardinality0..*
TypeReference(QuestionnaireResponse)
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.derivedFrom
Element IdObservation.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.

Short DisplayRelated resource from which the observation is made
Cardinality0..*
TypeReference(DocumentReference)
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.component
Element IdObservation.component
Definition

Used when reporting systolic and diastolic blood pressure.

Short DisplayUsed when reporting systolic and diastolic blood pressure.
Cardinality0..* This element is affected by the following invariants: obs-7
TypeBackboneElement
Must Supporttrue
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.

Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
vs-3RuleIf there is no a value a data absent reason must be presentvalue.exists() or dataAbsentReason.exists()
Observation.component.id
Element IdObservation.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.

Short DisplayUnique id for inter-element referencing
Cardinality0..1 This element is affected by the following invariants: ele-1
Typestring
Observation.component.extension
Element IdObservation.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 managable, 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.

Short DisplayAdditional content defined by implementations
Cardinality0..*
TypeExtension
Alternate Namesextensions, user content
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.component.modifierExtension
Element IdObservation.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 managable, 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).

Short DisplayExtensions that cannot be ignored even if unrecognized
Cardinality0..*
TypeExtension
Is Modifiertrue (Reason: Modifier extensions are expected to modify the meaning or interpretation of the element that contains them)
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
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.component.code
Element IdObservation.component.code
Definition

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

Short DisplayType of component observation (code / type)
Cardinality1..1 This element is affected by the following invariants: obs-7
Terminology BindingThis identifies the vital sign result type. Original source C-CDA R1.1 , HITSP Vital Sign Result Type.
The codes SHALL be taken from Vital Signs; other codes may be used where these codes are not suitable
TypeCodeableConcept
Must Supporttrue
Requirements

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

Comments

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

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.component.value[x]
Element IdObservation.component.value[x]
Definition

Vital Sign Value.

Short DisplayVital Sign Value
Cardinality0..1 This element is affected by the following invariants: vs-3
TypeChoice of: Quantity, CodeableConcept, string, boolean, integer, Range, Ratio, SampledData, time, dateTime, Period, Attachment, Reference(MolecularSequence)
[x] NoteSee Choice of Datatypes for further information about how to use [x]
Must Supporttrue
Requirements
  1. SHALL contain exactly one [1..1] value with @xsi:type="PQ" (CONF:7305).
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 the code.
  • 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 code defines a coded value.
  • Attachment is used if the observation result value is a binary file such as an image. If the observation result value is derived from the binary file (for example 'X' detected and here is the the proof in this image), the binary file may be directly represented using DocumentReference and referenced by derivedFrom.
  • If a value is present, the datatype for this element should be determined by the code.
  • 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 code defines a coded value.
  • Attachment is used if the observation result value is a binary file such as an image. If the observation result value is derived from the binary file (for example 'X' detected and here is the the proof in this image), the binary file may be directly represented using DocumentReference and referenced by derivedFrom.
  • The usage of valueReference is restricted to the MolecularSequence resource when used as a definitional resource, not as a patient-specific finding. .
  • For additional guidance, see the Notes section below.
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
SlicingThis element introduces a set of slices. The slicing rules are:
  • unordered
  • Open
  • discriminators: type:$this
Observation.component.value[x](valueQuantity)
Element IdObservation.component.value[x]:valueQuantity
Definition

Vital Sign Value recorded with UCUM.

Short DisplayVital Sign Value recorded with UCUM
Cardinality0..1
Terminology BindingCommonly encountered UCUM units for recording Vital Signs.
The codes SHALL be taken from Vital Signs Units
TypeQuantity
[x] NoteSee Choice of Datatypes for further information about how to use [x]
Must Supporttrue
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.

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 the code.
  • 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 code defines a coded value.
  • Attachment is used if the observation result value is a binary file such as an image. If the observation result value is derived from the binary file (for example 'X' detected and here is the the proof in this image), the binary file may be directly represented using DocumentReference and referenced by derivedFrom.
  • If a value is present, the datatype for this element should be determined by the code.
  • 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 code defines a coded value.
  • Attachment is used if the observation result value is a binary file such as an image. If the observation result value is derived from the binary file (for example 'X' detected and here is the the proof in this image), the binary file may be directly represented using DocumentReference and referenced by derivedFrom.
  • The usage of valueReference is restricted to the MolecularSequence resource when used as a definitional resource, not as a patient-specific finding. .
  • For additional guidance, see the Notes section below.
Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.component.dataAbsentReason
Element IdObservation.component.dataAbsentReason
Definition

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

Short DisplayWhy the component result value is missing
Cardinality0..1 This element is affected by the following invariants: vs-3
Terminology BindingCodes specifying why the result (`Observation.value[x]`) is missing.
The codes SHALL be taken from Data Absent Reason; other codes may be used where these codes are not suitable
TypeCodeableConcept
Must Supporttrue
Requirements

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

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.component.interpretation
Element IdObservation.component.interpretation
Definition

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

Short DisplayHigh, low, normal, etc
Cardinality0..*
Terminology BindingCodes identifying interpretations of observations.
The codes SHALL be taken from Observation Interpretation Codes; other codes may be used where these codes are not suitable
TypeCodeableConcept
Requirements

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

Alternate NamesAbnormal Flag
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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())
Observation.component.referenceRange
Element IdObservation.component.referenceRange
Definition

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

Short DisplayProvides guide for interpretation of component result value
Cardinality0..*
TypeSee ttp://hl7.org/fhir/StructureDefinition/Observation#Observation.referenceRange
Requirements

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

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.

Invariants
Inherited by this element
ele-1RuleAll FHIR elements must have a @value or childrenhasValue() or (children().count() > id.count())