Summary
Request & Response
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Other
Conformance
Terminology
Documents
Definitional Artifacts
Medication Definition
Evidence-Based Medicine
Quality Reporting & Testing
Public Health & Research
Complex
Primitive
ActivityDefinition
CanonicalResource
CapabilityStatement
ChargeItemDefinition
Claim
CodeSystem
Composition
ConceptMap
CoverageEligibilityRequest
DocumentReference
Encounter
EpisodeOfCare
Group
Library
List
Measure
MedicinalProductDefinition
MessageHeader
NamingSystem
Observation
Patient
PlanDefinition
Resource
SpecimenDefinition
StructureDefinition
StructureMap
Subscription
ValueSet
default
Set of definitional characteristics for a kind of observation or measurement produced or consumed by an orderable health care service.
ObservationDefinition
Path
ObservationDefinition
Id
ObservationDefinition
Cardinality
0 - *
Definition
Set of definitional characteristics for a kind of observation or measurement produced or consumed by an orderable health care service.
Comment
An instance of this resource informs the consumer of a health-related service (such as a lab diagnostic test or panel) about how the observations used or produced by this service will look like.
Constraint
cnl-0 [warning]
Name should be usable as an identifier for the module by machine processing applications such as code generation
obd-0 [error]
If permittedUnit exists, then permittedDataType=Quantity must exist.
Path
ObservationDefinition.url
Id
ObservationDefinition.url
Type
Cardinality
0 - 1
Definition
An absolute URL that is used to identify this ObservationDefinition when it is referenced in a specification, model, design or an instance. This SHALL be a URL, SHOULD be globally unique, and SHOULD be an address at which this ObservationDefinition is (or will be) published. The URL SHOULD include the major version of the ObservationDefinition. For more information see Technical and Business Versions.
Comment
Can be a urn:uuid: or a urn:oid:, but real http: addresses are preferred. This is the URI that will be used when making canonical references to this resource.
Requirements
Allows the ObservationDefinition to be referenced by a single globally unique identifier.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier
Id
ObservationDefinition.identifier
Type
Cardinality
0 - 1
Definition
Business identifiers assigned to this ObservationDefinition. by the performer and/or other systems. These identifiers remain constant as the resource is updated and propagates from server to server.
Comment
This is a business identifier, not a resource identifier. It is best practice for the identifier to only appear on a single resource instance, however business practices may occasionally dictate that multiple resource instances with the same identifier can exist - possibly even with different resource types.
Requirements
Allows identification of the ObservationDefinition as it is known by various participating systems and in a way that remains consistent across servers.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.use
Id
Identifier.use
Type
Cardinality
0 - 1
Definition
The purpose of this identifier.
Comment
Applications can assume that an identifier is permanent unless it explicitly says that it is temporary.
Requirements
Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers.
Binding
Strength
required
Description
Identifies the purpose for this identifier, if known .
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.type
Id
Identifier.type
Type
Cardinality
0 - 1
Definition
A coded type for the identifier that can be used to determine which identifier to use for a specific purpose.
Comment
This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type.
Requirements
Allows users to make use of identifiers when the identifier system is not known.
Binding
Strength
extensible
Description
A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.type.CodeableConcept.coding
Id
CodeableConcept.coding
Type
Cardinality
0 - *
Definition
A reference to a code defined by a terminology system.
Comment
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.
Requirements
Allows for alternative encodings within a code system, and translations to other code systems.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.type.CodeableConcept.coding.Coding.system
Id
Coding.system
Type
Cardinality
0 - 1
Definition
The identification of the code system that defines the meaning of the symbol in the code.
Comment
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.
Requirements
Need to be unambiguous about the source of the definition of the symbol.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.type.CodeableConcept.coding.Coding.version
Id
Coding.version
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.type.CodeableConcept.coding.Coding.code
Id
Coding.code
Type
Cardinality
0 - 1
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).
Comment
Requirements
Need to refer to a particular code in the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.identifier.Identifier.type.CodeableConcept.coding.Coding.display
Id
Coding.display
Type
Cardinality
0 - 1
Definition
A representation of the meaning of the code in the system, following the rules of the system.
Comment
Requirements
Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.identifier.Identifier.type.CodeableConcept.coding.Coding.userSelected
Id
Coding.userSelected
Type
Cardinality
0 - 1
Definition
Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.system
Id
Identifier.system
Type
Cardinality
0 - 1
Definition
Establishes the namespace for the value - that is, an absolute URL that describes a set values that are unique.
Comment
Identifier.system is always case sensitive.
Requirements
There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.value
Id
Identifier.value
Type
Cardinality
0 - 1
Definition
The portion of the identifier typically relevant to the user and which is unique within the context of the system.
Comment
If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the [http://hl7.org/fhir/StructureDefinition/rendered-value](http://hl7.org/fhir/extensions/StructureDefinition-rendered-value.html)). Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ident-1
Path
ObservationDefinition.identifier.Identifier.period
Id
Identifier.period
Type
Cardinality
0 - 1
Definition
Time period during which identifier is/was valid for use.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.period.Period.start
Id
Period.start
Type
Cardinality
0 - 1
Definition
The start of the period. The boundary is inclusive.
Comment
If the low element is missing, the meaning is that the low boundary is not known.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
per-1
Path
ObservationDefinition.identifier.Identifier.period.Period.end
Id
Period.end
Type
Cardinality
0 - 1
Definition
The end of the period. If the end of the period is missing, it means no end was known or planned at the time the instance was created. The start may be in the past, and the end date in the future, which means that period is expected/planned to end at that time.
Comment
The end value includes any matching date/time. i.e. 2012-02-03T10:00:00 is in a period that has an end value of 2012-02-03.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
per-1
Path
ObservationDefinition.identifier.Identifier.assigner
Id
Identifier.assigner
Type
Cardinality
0 - 1
Definition
Organization that issued/manages the identifier.
Comment
The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.assigner.Reference.reference
Id
Reference.reference
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
ref-1
Path
ObservationDefinition.identifier.Identifier.assigner.Reference.type
Id
Reference.type
Type
Cardinality
0 - 1
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).
Comment
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 known RESTful URL) or by resolving the target of the reference.
Binding
Strength
extensible
Description
Aa resource (or, for logical models, the URI of the logical model).
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.assigner.Reference.identifier
Id
Reference.identifier
Type
Cardinality
0 - 1
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.
Comment
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).
This element only allows for a single identifier. In the case where additional identifers are required, use the [http://hl7.org/fhir/StructureDefinition/additionalIdentifier](http://hl7.org/fhir/extensions/StructureDefinition-additionalIdentifier.html) extension.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
Path
ObservationDefinition.identifier.Identifier.assigner.Reference.identifier.Identifier.use
Id
Identifier.use
Type
Cardinality
0 - 1
Definition
The purpose of this identifier.
Comment
Applications can assume that an identifier is permanent unless it explicitly says that it is temporary.
Requirements
Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers.
Binding
Strength
required
Description
Identifies the purpose for this identifier, if known .
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.assigner.Reference.identifier.Identifier.type
Id
Identifier.type
Type
Cardinality
0 - 1
Definition
A coded type for the identifier that can be used to determine which identifier to use for a specific purpose.
Comment
This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type.
Requirements
Allows users to make use of identifiers when the identifier system is not known.
Binding
Strength
extensible
Description
A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.assigner.Reference.identifier.Identifier.system
Id
Identifier.system
Type
Cardinality
0 - 1
Definition
Establishes the namespace for the value - that is, an absolute URL that describes a set values that are unique.
Comment
Identifier.system is always case sensitive.
Requirements
There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.assigner.Reference.identifier.Identifier.value
Id
Identifier.value
Type
Cardinality
0 - 1
Definition
The portion of the identifier typically relevant to the user and which is unique within the context of the system.
Comment
If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the [http://hl7.org/fhir/StructureDefinition/rendered-value](http://hl7.org/fhir/extensions/StructureDefinition-rendered-value.html)). Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ident-1
Path
ObservationDefinition.identifier.Identifier.assigner.Reference.identifier.Identifier.period
Id
Identifier.period
Type
Cardinality
0 - 1
Definition
Time period during which identifier is/was valid for use.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.assigner.Reference.identifier.Identifier.assigner
Id
Identifier.assigner
Type
Cardinality
0 - 1
Definition
Organization that issued/manages the identifier.
Comment
The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.identifier.Identifier.assigner.Reference.display
Id
Reference.display
Type
Cardinality
0 - 1
Definition
Plain text narrative that identifies the resource in addition to the resource reference.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
Path
ObservationDefinition.version
Id
ObservationDefinition.version
Type
Cardinality
0 - 1
Definition
The identifier that is used to identify this version of the ObservationDefinition when it is referenced in a specification, model, design or instance. This is an arbitrary value managed by the ObservationDefinition author and is not expected to be globally unique. For example, it might be a timestamp (e.g. yyyymmdd) if a managed version is not available. There is also no expectation that versions are orderable.
Comment
There may be multiple different instances of an observationDefinition that have the same identifier but different versions.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.versionAlgorithm[x]
Id
ObservationDefinition.versionAlgorithm[x]
Type
Cardinality
0 - 1
Definition
Indicates the mechanism used to compare versions to determine which is more current.
Comment
If set as a string, this is a FHIRPath expression that has two additional context variables passed in - %version1 and %version2 and will return a negative number if version1 is newer, a positive number if version2 and a 0 if the version ordering can't be successfully be determined.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.name
Id
ObservationDefinition.name
Type
Cardinality
0 - 1
Definition
A natural language name identifying the ObservationDefinition. This name should be usable as an identifier for the module by machine processing applications such as code generation.
Comment
The name is not expected to be globally unique. The name should be a simple alphanumeric type name to ensure that it is machine-processing friendly.
Requirements
Support human navigation and code generation.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cnl-0
Path
ObservationDefinition.title
Id
ObservationDefinition.title
Type
Cardinality
0 - 1
Definition
A short, descriptive, user-friendly title for the ObservationDefinition.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.status
Id
ObservationDefinition.status
Type
Cardinality
1 - 1
Definition
The current state of the ObservationDefinition.
Comment
A nominal state-transition diagram can be found in the [Definition pattern](definition.html#statemachine) documentation
Unknown does not represent "other" - one of the defined statuses must apply. Unknown is used when the authoring system is not sure what the current status is.
See guidance around (not) making local changes to elements [here](canonicalresource.html#localization).
Binding
Strength
required
Description
Codes identifying the state of an ObservationDefinition.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.experimental
Id
ObservationDefinition.experimental
Type
Cardinality
0 - 1
Definition
A flag to indicate that this ObservationDefinition is authored for testing purposes (or education/evaluation/marketing), and is not intended to be used for genuine usage.
Comment
Allows filtering of ObservationDefinition that are appropriate for use vs. not.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.date
Id
ObservationDefinition.date
Type
Cardinality
0 - 1
Definition
The date (and optionally time) when the ObservationDefinition was last significantly changed. The date must change when the business version changes and it must change if the status code changes. In addition, it should change when the substantive content of the ObservationDefinition changes.
Comment
The date is often not tracked until the resource is published, but may be present on draft content. Note that this is not the same as the resource last-modified-date, since the resource may be a secondary representation of the ObservationDefinition. Additional specific dates may be added as extensions or be found by consulting Provenances associated with past versions of the resource.
See guidance around (not) making local changes to elements [here](canonicalresource.html#localization).
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
publisher
The name of the individual or organization that published the ObservationDefinition
Path
ObservationDefinition.publisher
Id
ObservationDefinition.publisher
Type
Cardinality
0 - 1
Definition
Helps establish the "authority/credibility" of the ObservationDefinition. May also allow for contact.
Comment
Requirements
Usually an organization, but may be an individual. The publisher (or steward) of the ObservationDefinition is the organization or individual primarily responsible for the maintenance and upkeep of the ObservationDefinition. This is not necessarily the same individual or organization that developed and initially authored the content. The publisher is the primary point of contact for questions or issues with the ObservationDefinition. This item SHOULD be populated unless the information is available from context.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.contact
Id
ObservationDefinition.contact
Type
Cardinality
0 - *
Definition
Contact details to assist a user in finding and communicating with the publisher.
Comment
May be a web site, an email address, a telephone number, etc.
See guidance around (not) making local changes to elements [here](canonicalresource.html#localization).
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.contact.ContactDetail.name
Id
ContactDetail.name
Type
Cardinality
0 - 1
Definition
The name of an individual to contact.
Comment
If there is no named individual, the telecom information is for the organization as a whole.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.contact.ContactDetail.telecom
Id
ContactDetail.telecom
Type
Cardinality
0 - *
Definition
The contact details for the individual (if a name was provided) or the organization.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.contact.ContactDetail.telecom.ContactPoint.system
Id
ContactPoint.system
Type
Cardinality
0 - 1
Definition
Telecommunications form for contact point - what communications system is required to make use of the contact.
Comment
Binding
Strength
required
Description
Telecommunications form for contact point.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cpt-2
Path
ObservationDefinition.contact.ContactDetail.telecom.ContactPoint.value
Id
ContactPoint.value
Type
Cardinality
0 - 1
Definition
The actual contact point details, in a form that is meaningful to the designated communication system (i.e. phone number or email address).
Comment
Additional text data such as phone extension numbers, or notes about use of the contact are sometimes included in the value.
Requirements
Need to support legacy numbers that are not in a tightly controlled format.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cpt-2
Path
ObservationDefinition.contact.ContactDetail.telecom.ContactPoint.use
Id
ContactPoint.use
Type
Cardinality
0 - 1
Definition
Identifies the purpose for the contact point.
Comment
Applications can assume that a contact is current unless it explicitly says that it is temporary or old.
Requirements
Need to track the way a person uses this contact, so a user can choose which is appropriate for their purpose.
Binding
Strength
required
Description
Use of contact point.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.contact.ContactDetail.telecom.ContactPoint.rank
Id
ContactPoint.rank
Type
Cardinality
0 - 1
Definition
Specifies a preferred order in which to use a set of contacts. ContactPoints with lower rank values are more preferred than those with higher rank values.
Comment
Note that rank does not necessarily follow the order in which the contacts are represented in the instance.
Ranks need not be unique. E.g. it's possible to have multiple contacts with rank=1. If the ranks have different systems or uses, this would be interpreted to mean "X is my most preferred phone number, Y is my most preferred email address" or "X is my preferred home email and Y is my preferred work email". If the system and use for equally-ranked contacts are the same, then the level of preference is equivalent for both repetitions.
Ranks need not be sequential and not all repetitions must have a rank. For example, it's possible to have 4 contacts with ranks of 2, 5 and two with no rank specified. That would be interpreted to mean the first is preferred over the second and no preference stated for the remaining contacts.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.contact.ContactDetail.telecom.ContactPoint.period
Id
ContactPoint.period
Type
Cardinality
0 - 1
Definition
Time period when the contact point was/is in use.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.contact.ContactDetail.telecom.ContactPoint.period.Period.start
Id
Period.start
Type
Cardinality
0 - 1
Definition
The start of the period. The boundary is inclusive.
Comment
If the low element is missing, the meaning is that the low boundary is not known.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
per-1
Path
ObservationDefinition.contact.ContactDetail.telecom.ContactPoint.period.Period.end
Id
Period.end
Type
Cardinality
0 - 1
Definition
The end of the period. If the end of the period is missing, it means no end was known or planned at the time the instance was created. The start may be in the past, and the end date in the future, which means that period is expected/planned to end at that time.
Comment
The end value includes any matching date/time. i.e. 2012-02-03T10:00:00 is in a period that has an end value of 2012-02-03.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
per-1
Path
ObservationDefinition.description
Id
ObservationDefinition.description
Type
Cardinality
0 - 1
Definition
A free text natural language description of the ObservationDefinition from the consumer's perspective.
Comment
This description can be used to capture details such as comments about misuse, instructions for clinical use and interpretation, literature references, examples from the paper world, etc. It is not a rendering of the module as conveyed in the text field of the resource itself. This item SHOULD be populated unless the information is available from context.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.useContext
Id
ObservationDefinition.useContext
Type
Cardinality
0 - *
Definition
The content was developed with a focus and intent of supporting the contexts that are listed. These contexts may be general categories (gender, age, ...) or may be references to specific programs (insurance plans, studies, ...) and may be used to assist with indexing and searching for appropriate ObservationDefinition instances.
Comment
When multiple usageContexts are specified, there is no expectation for whether all or any of the contexts apply.
Requirements
Assist in searching for appropriate content.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.useContext.UsageContext.code
Id
UsageContext.code
Type
Cardinality
1 - 1
Definition
A code that identifies the type of context being specified by this usage context.
Comment
Binding
Strength
extensible
Description
A code that specifies a type of context being specified by a usage context.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.useContext.UsageContext.code.Coding.system
Id
Coding.system
Type
Cardinality
0 - 1
Definition
The identification of the code system that defines the meaning of the symbol in the code.
Comment
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.
Requirements
Need to be unambiguous about the source of the definition of the symbol.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.useContext.UsageContext.code.Coding.version
Id
Coding.version
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.useContext.UsageContext.code.Coding.code
Id
Coding.code
Type
Cardinality
0 - 1
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).
Comment
Requirements
Need to refer to a particular code in the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.useContext.UsageContext.code.Coding.display
Id
Coding.display
Type
Cardinality
0 - 1
Definition
A representation of the meaning of the code in the system, following the rules of the system.
Comment
Requirements
Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.useContext.UsageContext.code.Coding.userSelected
Id
Coding.userSelected
Type
Cardinality
0 - 1
Definition
Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.useContext.UsageContext.value[x]
Id
UsageContext.value[x]
Type
Cardinality
1 - 1
Definition
A value that defines the context specified in this context of use. The interpretation of the value is defined by the code.
Comment
Binding
Strength
example
Description
A code that defines the specific value for the context being specified.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.useContext.UsageContext.value[x].CodeableConcept.coding
Id
CodeableConcept.coding
Type
Cardinality
0 - *
Definition
A reference to a code defined by a terminology system.
Comment
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.
Requirements
Allows for alternative encodings within a code system, and translations to other code systems.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.useContext.UsageContext.value[x].CodeableConcept.coding.Coding.system
Id
Coding.system
Type
Cardinality
0 - 1
Definition
The identification of the code system that defines the meaning of the symbol in the code.
Comment
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.
Requirements
Need to be unambiguous about the source of the definition of the symbol.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.useContext.UsageContext.value[x].CodeableConcept.coding.Coding.version
Id
Coding.version
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.useContext.UsageContext.value[x].CodeableConcept.coding.Coding.code
Id
Coding.code
Type
Cardinality
0 - 1
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).
Comment
Requirements
Need to refer to a particular code in the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.useContext.UsageContext.value[x].CodeableConcept.coding.Coding.display
Id
Coding.display
Type
Cardinality
0 - 1
Definition
A representation of the meaning of the code in the system, following the rules of the system.
Comment
Requirements
Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.useContext.UsageContext.value[x].CodeableConcept.coding.Coding.userSelected
Id
Coding.userSelected
Type
Cardinality
0 - 1
Definition
Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.jurisdiction
Id
ObservationDefinition.jurisdiction
Type
Cardinality
0 - *
Definition
A jurisdiction in which the ObservationDefinition is intended to be used.
Comment
It may be possible for the ObservationDefinition to be used in jurisdictions other than those for which it was originally designed or intended.
DEPRECATION NOTE: For consistency, implementations are encouraged to migrate to using the new 'jurisdiction' code in the useContext element. (I.e. useContext.code indicating http://terminology.hl7.org/CodeSystem/usage-context-type#jurisdiction and useContext.valueCodeableConcept indicating the jurisdiction.)
Binding
Strength
extensible
Description
Codes for country, country subdivision and region for indicating where a resource is intended to be used.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.jurisdiction.CodeableConcept.coding
Id
CodeableConcept.coding
Type
Cardinality
0 - *
Definition
A reference to a code defined by a terminology system.
Comment
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.
Requirements
Allows for alternative encodings within a code system, and translations to other code systems.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.jurisdiction.CodeableConcept.coding.Coding.system
Id
Coding.system
Type
Cardinality
0 - 1
Definition
The identification of the code system that defines the meaning of the symbol in the code.
Comment
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.
Requirements
Need to be unambiguous about the source of the definition of the symbol.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.jurisdiction.CodeableConcept.coding.Coding.version
Id
Coding.version
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.jurisdiction.CodeableConcept.coding.Coding.code
Id
Coding.code
Type
Cardinality
0 - 1
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).
Comment
Requirements
Need to refer to a particular code in the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.jurisdiction.CodeableConcept.coding.Coding.display
Id
Coding.display
Type
Cardinality
0 - 1
Definition
A representation of the meaning of the code in the system, following the rules of the system.
Comment
Requirements
Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.jurisdiction.CodeableConcept.coding.Coding.userSelected
Id
Coding.userSelected
Type
Cardinality
0 - 1
Definition
Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.purpose
Id
ObservationDefinition.purpose
Type
Cardinality
0 - 1
Definition
Explains why this ObservationDefinition is needed and why it has been designed as it has.
Comment
This element does not describe the usage of the ObservationDefinition. Rather it is for traceability of ''why'' the resource is either needed or ''why'' it is defined as it is. This may be used to point to source materials or specifications that drove the structure of this ObservationDefinition.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.copyright
Id
ObservationDefinition.copyright
Type
Cardinality
0 - 1
Definition
Copyright statement relating to the ObservationDefinition and/or its contents. Copyright statements are generally legal restrictions on the use and publishing of the ObservationDefinition.
Comment
Requirements
Consumers of the ObservationDefinition must be able to determine any legal restrictions on the use of the artifact and/or its content.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.copyrightLabel
Id
ObservationDefinition.copyrightLabel
Type
Cardinality
0 - 1
Definition
A short string (<50 characters), suitable for inclusion in a page footer that identifies the copyright holder, effective period, and optionally whether rights are resctricted. (e.g. 'All rights reserved', 'Some rights reserved').
Comment
The (c) symbol should NOT be included in this string. It will be added by software when rendering the notation. Full details about licensing, restrictions, warrantees, etc. goes in the more general 'copyright' element.
Requirements
Defines the content expected to be rendered in all representations of the artifact.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.approvalDate
Id
ObservationDefinition.approvalDate
Type
Cardinality
0 - 1
Definition
The date on which the asset content was approved by the publisher. Approval happens once when the content is officially approved for usage.
Comment
The date may be more recent than the approval date because of minor changes / editorial corrections.
See guidance around (not) making local changes to elements [here](canonicalresource.html#localization).
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.lastReviewDate
Id
ObservationDefinition.lastReviewDate
Type
Cardinality
0 - 1
Definition
The date on which the asset content was last reviewed. Review happens periodically after that, but doesn't change the original approval date.
Comment
If specified, this is usually after the approval date.
See guidance around (not) making local changes to elements [here](canonicalresource.html#localization).
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.effectivePeriod
Id
ObservationDefinition.effectivePeriod
Type
Cardinality
0 - 1
Definition
The period during which the ObservationDefinition content was or is planned to be effective.
Comment
The effective period for an ObservationDefinition determines when the content is applicable for usage and is independent of publication and review dates. For example, an observation definition intended to be used for the year 2021 might be published in 2020.
See guidance around (not) making local changes to elements [here](canonicalresource.html#localization).
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.effectivePeriod.Period.start
Id
Period.start
Type
Cardinality
0 - 1
Definition
The start of the period. The boundary is inclusive.
Comment
If the low element is missing, the meaning is that the low boundary is not known.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
per-1
Path
ObservationDefinition.effectivePeriod.Period.end
Id
Period.end
Type
Cardinality
0 - 1
Definition
The end of the period. If the end of the period is missing, it means no end was known or planned at the time the instance was created. The start may be in the past, and the end date in the future, which means that period is expected/planned to end at that time.
Comment
The end value includes any matching date/time. i.e. 2012-02-03T10:00:00 is in a period that has an end value of 2012-02-03.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
per-1
Path
ObservationDefinition.derivedFromCanonical
Id
ObservationDefinition.derivedFromCanonical
Type
Cardinality
0 - *
Definition
The canonical URL pointing to another FHIR-defined ObservationDefinition that is adhered to in whole or in part by this definition.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.derivedFromUri
Id
ObservationDefinition.derivedFromUri
Type
Cardinality
0 - *
Definition
The URL pointing to an externally-defined observation definition, guideline or other definition that is adhered to in whole or in part by this definition.
Comment
Requirements
Observation definitions may be refinements of other definitions.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.subject
Id
ObservationDefinition.subject
Type
Cardinality
0 - *
Definition
A code that describes the intended kind of subject of Observation instances conforming to this ObservationDefinition.
Comment
Examples: person, animal, device, air, surface ….
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.subject.CodeableConcept.coding
Id
CodeableConcept.coding
Type
Cardinality
0 - *
Definition
A reference to a code defined by a terminology system.
Comment
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.
Requirements
Allows for alternative encodings within a code system, and translations to other code systems.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.subject.CodeableConcept.coding.Coding.system
Id
Coding.system
Type
Cardinality
0 - 1
Definition
The identification of the code system that defines the meaning of the symbol in the code.
Comment
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.
Requirements
Need to be unambiguous about the source of the definition of the symbol.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.subject.CodeableConcept.coding.Coding.version
Id
Coding.version
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.subject.CodeableConcept.coding.Coding.code
Id
Coding.code
Type
Cardinality
0 - 1
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).
Comment
Requirements
Need to refer to a particular code in the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.subject.CodeableConcept.coding.Coding.display
Id
Coding.display
Type
Cardinality
0 - 1
Definition
A representation of the meaning of the code in the system, following the rules of the system.
Comment
Requirements
Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.subject.CodeableConcept.coding.Coding.userSelected
Id
Coding.userSelected
Type
Cardinality
0 - 1
Definition
Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.performerType
Id
ObservationDefinition.performerType
Type
Cardinality
0 - 1
Definition
The type of individual/organization/device that is expected to act upon instances of this definition.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.performerType.CodeableConcept.coding
Id
CodeableConcept.coding
Type
Cardinality
0 - *
Definition
A reference to a code defined by a terminology system.
Comment
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.
Requirements
Allows for alternative encodings within a code system, and translations to other code systems.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.performerType.CodeableConcept.coding.Coding.system
Id
Coding.system
Type
Cardinality
0 - 1
Definition
The identification of the code system that defines the meaning of the symbol in the code.
Comment
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.
Requirements
Need to be unambiguous about the source of the definition of the symbol.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.performerType.CodeableConcept.coding.Coding.version
Id
Coding.version
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.performerType.CodeableConcept.coding.Coding.code
Id
Coding.code
Type
Cardinality
0 - 1
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).
Comment
Requirements
Need to refer to a particular code in the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.performerType.CodeableConcept.coding.Coding.display
Id
Coding.display
Type
Cardinality
0 - 1
Definition
A representation of the meaning of the code in the system, following the rules of the system.
Comment
Requirements
Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.performerType.CodeableConcept.coding.Coding.userSelected
Id
Coding.userSelected
Type
Cardinality
0 - 1
Definition
Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.category
Id
ObservationDefinition.category
Type
Cardinality
0 - *
Definition
A code that classifies the general type of observation.
Comment
This element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used for one instance of ObservationDefinition. The level of granularity is defined by the category concepts in the value set.
Requirements
Used for filtering what kinds of observations are retrieved and displayed.
Binding
Strength
example
Description
Codes for high level observation categories.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.category.CodeableConcept.coding
Id
CodeableConcept.coding
Type
Cardinality
0 - *
Definition
A reference to a code defined by a terminology system.
Comment
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.
Requirements
Allows for alternative encodings within a code system, and translations to other code systems.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.category.CodeableConcept.coding.Coding.system
Id
Coding.system
Type
Cardinality
0 - 1
Definition
The identification of the code system that defines the meaning of the symbol in the code.
Comment
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.
Requirements
Need to be unambiguous about the source of the definition of the symbol.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.category.CodeableConcept.coding.Coding.version
Id
Coding.version
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.category.CodeableConcept.coding.Coding.code
Id
Coding.code
Type
Cardinality
0 - 1
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).
Comment
Requirements
Need to refer to a particular code in the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.category.CodeableConcept.coding.Coding.display
Id
Coding.display
Type
Cardinality
0 - 1
Definition
A representation of the meaning of the code in the system, following the rules of the system.
Comment
Requirements
Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.category.CodeableConcept.coding.Coding.userSelected
Id
Coding.userSelected
Type
Cardinality
0 - 1
Definition
Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.code
Id
ObservationDefinition.code
Type
Cardinality
1 - 1
Definition
Describes what will be observed. Sometimes this is called the observation "name".
Comment
Binding
Strength
example
Description
Codes identifying names of simple observations.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.code.CodeableConcept.coding
Id
CodeableConcept.coding
Type
Cardinality
0 - *
Definition
A reference to a code defined by a terminology system.
Comment
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.
Requirements
Allows for alternative encodings within a code system, and translations to other code systems.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.code.CodeableConcept.coding.Coding.system
Id
Coding.system
Type
Cardinality
0 - 1
Definition
The identification of the code system that defines the meaning of the symbol in the code.
Comment
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.
Requirements
Need to be unambiguous about the source of the definition of the symbol.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.code.CodeableConcept.coding.Coding.version
Id
Coding.version
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.code.CodeableConcept.coding.Coding.code
Id
Coding.code
Type
Cardinality
0 - 1
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).
Comment
Requirements
Need to refer to a particular code in the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.code.CodeableConcept.coding.Coding.display
Id
Coding.display
Type
Cardinality
0 - 1
Definition
A representation of the meaning of the code in the system, following the rules of the system.
Comment
Requirements
Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.code.CodeableConcept.coding.Coding.userSelected
Id
Coding.userSelected
Type
Cardinality
0 - 1
Definition
Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
permittedDataType
Quantity | CodeableConcept | string | boolean | integer | Range | Ratio | SampledData | time | dateTime | Period
Path
ObservationDefinition.permittedDataType
Id
ObservationDefinition.permittedDataType
Type
Cardinality
0 - *
Definition
The data types allowed for the value element of the instance observations conforming to this ObservationDefinition.
Comment
Binding
Strength
required
Description
Permitted data type for observation value.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
obd-0
Path
ObservationDefinition.multipleResultsAllowed
Id
ObservationDefinition.multipleResultsAllowed
Type
Cardinality
0 - 1
Definition
Multiple results allowed for observations conforming to this ObservationDefinition.
Comment
An example of observation allowing multiple results is "bacteria identified by culture". Conversely, the measurement of a potassium level allows a single result.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.bodySite
Id
ObservationDefinition.bodySite
Type
Cardinality
0 - 1
Definition
The site on the subject's body where the observation is to be made.
Comment
Only used if the defined observation is to be made directly on a body part and if this body part is not implied by code found in ObservationDefinition.code. Not used for in vitro diagnostic observations.
Example: 14975008 |Forearm structure|.
Binding
Strength
example
Description
SNOMED CT body structures.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.bodySite.CodeableConcept.coding
Id
CodeableConcept.coding
Type
Cardinality
0 - *
Definition
A reference to a code defined by a terminology system.
Comment
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.
Requirements
Allows for alternative encodings within a code system, and translations to other code systems.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.bodySite.CodeableConcept.coding.Coding.system
Id
Coding.system
Type
Cardinality
0 - 1
Definition
The identification of the code system that defines the meaning of the symbol in the code.
Comment
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.
Requirements
Need to be unambiguous about the source of the definition of the symbol.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.bodySite.CodeableConcept.coding.Coding.version
Id
Coding.version
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.bodySite.CodeableConcept.coding.Coding.code
Id
Coding.code
Type
Cardinality
0 - 1
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).
Comment
Requirements
Need to refer to a particular code in the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.bodySite.CodeableConcept.coding.Coding.display
Id
Coding.display
Type
Cardinality
0 - 1
Definition
A representation of the meaning of the code in the system, following the rules of the system.
Comment
Requirements
Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.bodySite.CodeableConcept.coding.Coding.userSelected
Id
Coding.userSelected
Type
Cardinality
0 - 1
Definition
Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.method
Id
ObservationDefinition.method
Type
Cardinality
0 - 1
Definition
The method or technique used to perform the observation.
Comment
Only used if not implicit in observation code
Example: 702659008 |Automated count technique|.
Requirements
In some cases, method can impact results.
Binding
Strength
example
Description
Methods for simple observations.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.method.CodeableConcept.coding
Id
CodeableConcept.coding
Type
Cardinality
0 - *
Definition
A reference to a code defined by a terminology system.
Comment
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.
Requirements
Allows for alternative encodings within a code system, and translations to other code systems.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.method.CodeableConcept.coding.Coding.system
Id
Coding.system
Type
Cardinality
0 - 1
Definition
The identification of the code system that defines the meaning of the symbol in the code.
Comment
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.
Requirements
Need to be unambiguous about the source of the definition of the symbol.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.method.CodeableConcept.coding.Coding.version
Id
Coding.version
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.method.CodeableConcept.coding.Coding.code
Id
Coding.code
Type
Cardinality
0 - 1
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).
Comment
Requirements
Need to refer to a particular code in the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.method.CodeableConcept.coding.Coding.display
Id
Coding.display
Type
Cardinality
0 - 1
Definition
A representation of the meaning of the code in the system, following the rules of the system.
Comment
Requirements
Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.method.CodeableConcept.coding.Coding.userSelected
Id
Coding.userSelected
Type
Cardinality
0 - 1
Definition
Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.specimen
Id
ObservationDefinition.specimen
Type
Cardinality
0 - *
Definition
The kind of specimen that this type of observation is produced on.
Comment
Only used for in vitro observations. When multiple occurrences of specimen are present, they are to be combined with a logical AND: all specified specimens are needed for the observation.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.specimen.Reference.reference
Id
Reference.reference
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
ref-1
Path
ObservationDefinition.specimen.Reference.type
Id
Reference.type
Type
Cardinality
0 - 1
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).
Comment
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 known RESTful URL) or by resolving the target of the reference.
Binding
Strength
extensible
Description
Aa resource (or, for logical models, the URI of the logical model).
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.specimen.Reference.identifier
Id
Reference.identifier
Type
Cardinality
0 - 1
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.
Comment
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).
This element only allows for a single identifier. In the case where additional identifers are required, use the [http://hl7.org/fhir/StructureDefinition/additionalIdentifier](http://hl7.org/fhir/extensions/StructureDefinition-additionalIdentifier.html) extension.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
Path
ObservationDefinition.specimen.Reference.identifier.Identifier.use
Id
Identifier.use
Type
Cardinality
0 - 1
Definition
The purpose of this identifier.
Comment
Applications can assume that an identifier is permanent unless it explicitly says that it is temporary.
Requirements
Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers.
Binding
Strength
required
Description
Identifies the purpose for this identifier, if known .
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.specimen.Reference.identifier.Identifier.type
Id
Identifier.type
Type
Cardinality
0 - 1
Definition
A coded type for the identifier that can be used to determine which identifier to use for a specific purpose.
Comment
This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type.
Requirements
Allows users to make use of identifiers when the identifier system is not known.
Binding
Strength
extensible
Description
A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.specimen.Reference.identifier.Identifier.type.CodeableConcept.coding
Id
CodeableConcept.coding
Type
Cardinality
0 - *
Definition
A reference to a code defined by a terminology system.
Comment
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.
Requirements
Allows for alternative encodings within a code system, and translations to other code systems.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.specimen.Reference.identifier.Identifier.system
Id
Identifier.system
Type
Cardinality
0 - 1
Definition
Establishes the namespace for the value - that is, an absolute URL that describes a set values that are unique.
Comment
Identifier.system is always case sensitive.
Requirements
There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.specimen.Reference.identifier.Identifier.value
Id
Identifier.value
Type
Cardinality
0 - 1
Definition
The portion of the identifier typically relevant to the user and which is unique within the context of the system.
Comment
If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the [http://hl7.org/fhir/StructureDefinition/rendered-value](http://hl7.org/fhir/extensions/StructureDefinition-rendered-value.html)). Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ident-1
Path
ObservationDefinition.specimen.Reference.identifier.Identifier.period
Id
Identifier.period
Type
Cardinality
0 - 1
Definition
Time period during which identifier is/was valid for use.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.specimen.Reference.identifier.Identifier.period.Period.start
Id
Period.start
Type
Cardinality
0 - 1
Definition
The start of the period. The boundary is inclusive.
Comment
If the low element is missing, the meaning is that the low boundary is not known.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
per-1
Path
ObservationDefinition.specimen.Reference.identifier.Identifier.period.Period.end
Id
Period.end
Type
Cardinality
0 - 1
Definition
The end of the period. If the end of the period is missing, it means no end was known or planned at the time the instance was created. The start may be in the past, and the end date in the future, which means that period is expected/planned to end at that time.
Comment
The end value includes any matching date/time. i.e. 2012-02-03T10:00:00 is in a period that has an end value of 2012-02-03.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
per-1
Path
ObservationDefinition.specimen.Reference.identifier.Identifier.assigner
Id
Identifier.assigner
Type
Cardinality
0 - 1
Definition
Organization that issued/manages the identifier.
Comment
The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.specimen.Reference.identifier.Identifier.assigner.Reference.reference
Id
Reference.reference
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
ref-1
Path
ObservationDefinition.specimen.Reference.identifier.Identifier.assigner.Reference.type
Id
Reference.type
Type
Cardinality
0 - 1
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).
Comment
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 known RESTful URL) or by resolving the target of the reference.
Binding
Strength
extensible
Description
Aa resource (or, for logical models, the URI of the logical model).
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.specimen.Reference.identifier.Identifier.assigner.Reference.identifier
Id
Reference.identifier
Type
Cardinality
0 - 1
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.
Comment
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).
This element only allows for a single identifier. In the case where additional identifers are required, use the [http://hl7.org/fhir/StructureDefinition/additionalIdentifier](http://hl7.org/fhir/extensions/StructureDefinition-additionalIdentifier.html) extension.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
Path
ObservationDefinition.specimen.Reference.identifier.Identifier.assigner.Reference.display
Id
Reference.display
Type
Cardinality
0 - 1
Definition
Plain text narrative that identifies the resource in addition to the resource reference.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
Path
ObservationDefinition.specimen.Reference.display
Id
Reference.display
Type
Cardinality
0 - 1
Definition
Plain text narrative that identifies the resource in addition to the resource reference.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
Path
ObservationDefinition.device
Id
ObservationDefinition.device
Type
Cardinality
0 - *
Definition
The measurement model of device or actual device used to produce observations of this type.
Comment
When multiple occurrences of device are present, they are to be combined with a logical OR: at least one of the specified devices is used to produce the observation.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.device.Reference.reference
Id
Reference.reference
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
ref-1
Path
ObservationDefinition.device.Reference.type
Id
Reference.type
Type
Cardinality
0 - 1
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).
Comment
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 known RESTful URL) or by resolving the target of the reference.
Binding
Strength
extensible
Description
Aa resource (or, for logical models, the URI of the logical model).
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.device.Reference.identifier
Id
Reference.identifier
Type
Cardinality
0 - 1
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.
Comment
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).
This element only allows for a single identifier. In the case where additional identifers are required, use the [http://hl7.org/fhir/StructureDefinition/additionalIdentifier](http://hl7.org/fhir/extensions/StructureDefinition-additionalIdentifier.html) extension.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
Path
ObservationDefinition.device.Reference.identifier.Identifier.use
Id
Identifier.use
Type
Cardinality
0 - 1
Definition
The purpose of this identifier.
Comment
Applications can assume that an identifier is permanent unless it explicitly says that it is temporary.
Requirements
Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers.
Binding
Strength
required
Description
Identifies the purpose for this identifier, if known .
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.device.Reference.identifier.Identifier.type
Id
Identifier.type
Type
Cardinality
0 - 1
Definition
A coded type for the identifier that can be used to determine which identifier to use for a specific purpose.
Comment
This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type.
Requirements
Allows users to make use of identifiers when the identifier system is not known.
Binding
Strength
extensible
Description
A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.device.Reference.identifier.Identifier.type.CodeableConcept.coding
Id
CodeableConcept.coding
Type
Cardinality
0 - *
Definition
A reference to a code defined by a terminology system.
Comment
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.
Requirements
Allows for alternative encodings within a code system, and translations to other code systems.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.device.Reference.identifier.Identifier.system
Id
Identifier.system
Type
Cardinality
0 - 1
Definition
Establishes the namespace for the value - that is, an absolute URL that describes a set values that are unique.
Comment
Identifier.system is always case sensitive.
Requirements
There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.device.Reference.identifier.Identifier.value
Id
Identifier.value
Type
Cardinality
0 - 1
Definition
The portion of the identifier typically relevant to the user and which is unique within the context of the system.
Comment
If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the [http://hl7.org/fhir/StructureDefinition/rendered-value](http://hl7.org/fhir/extensions/StructureDefinition-rendered-value.html)). Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ident-1
Path
ObservationDefinition.device.Reference.identifier.Identifier.period
Id
Identifier.period
Type
Cardinality
0 - 1
Definition
Time period during which identifier is/was valid for use.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.device.Reference.identifier.Identifier.period.Period.start
Id
Period.start
Type
Cardinality
0 - 1
Definition
The start of the period. The boundary is inclusive.
Comment
If the low element is missing, the meaning is that the low boundary is not known.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
per-1
Path
ObservationDefinition.device.Reference.identifier.Identifier.period.Period.end
Id
Period.end
Type
Cardinality
0 - 1
Definition
The end of the period. If the end of the period is missing, it means no end was known or planned at the time the instance was created. The start may be in the past, and the end date in the future, which means that period is expected/planned to end at that time.
Comment
The end value includes any matching date/time. i.e. 2012-02-03T10:00:00 is in a period that has an end value of 2012-02-03.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
per-1
Path
ObservationDefinition.device.Reference.identifier.Identifier.assigner
Id
Identifier.assigner
Type
Cardinality
0 - 1
Definition
Organization that issued/manages the identifier.
Comment
The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.device.Reference.identifier.Identifier.assigner.Reference.reference
Id
Reference.reference
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
ref-1
Path
ObservationDefinition.device.Reference.identifier.Identifier.assigner.Reference.type
Id
Reference.type
Type
Cardinality
0 - 1
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).
Comment
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 known RESTful URL) or by resolving the target of the reference.
Binding
Strength
extensible
Description
Aa resource (or, for logical models, the URI of the logical model).
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.device.Reference.identifier.Identifier.assigner.Reference.identifier
Id
Reference.identifier
Type
Cardinality
0 - 1
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.
Comment
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).
This element only allows for a single identifier. In the case where additional identifers are required, use the [http://hl7.org/fhir/StructureDefinition/additionalIdentifier](http://hl7.org/fhir/extensions/StructureDefinition-additionalIdentifier.html) extension.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
Path
ObservationDefinition.device.Reference.identifier.Identifier.assigner.Reference.display
Id
Reference.display
Type
Cardinality
0 - 1
Definition
Plain text narrative that identifies the resource in addition to the resource reference.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
Path
ObservationDefinition.device.Reference.display
Id
Reference.display
Type
Cardinality
0 - 1
Definition
Plain text narrative that identifies the resource in addition to the resource reference.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
Path
ObservationDefinition.preferredReportName
Id
ObservationDefinition.preferredReportName
Type
Cardinality
0 - 1
Definition
The preferred name to be used when reporting the results of observations conforming to this ObservationDefinition.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.permittedUnit
Id
ObservationDefinition.permittedUnit
Type
Cardinality
0 - *
Definition
Units allowed for the valueQuantity element in the instance observations conforming to this ObservationDefinition.
Comment
Binding
Strength
preferred
Description
Codes identifying units of measure.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
obd-0
Path
ObservationDefinition.permittedUnit.Coding.system
Id
Coding.system
Type
Cardinality
0 - 1
Definition
The identification of the code system that defines the meaning of the symbol in the code.
Comment
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.
Requirements
Need to be unambiguous about the source of the definition of the symbol.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.permittedUnit.Coding.version
Id
Coding.version
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.permittedUnit.Coding.code
Id
Coding.code
Type
Cardinality
0 - 1
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).
Comment
Requirements
Need to refer to a particular code in the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.permittedUnit.Coding.display
Id
Coding.display
Type
Cardinality
0 - 1
Definition
A representation of the meaning of the code in the system, following the rules of the system.
Comment
Requirements
Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.permittedUnit.Coding.userSelected
Id
Coding.userSelected
Type
Cardinality
0 - 1
Definition
Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue
Id
ObservationDefinition.qualifiedValue
Type
Cardinality
0 - *
Definition
A set of qualified values associated with a context and a set of conditions - provides a range for quantitative and ordinal observations and a collection of value sets for qualitative observations.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.context
Id
ObservationDefinition.qualifiedValue.context
Type
Cardinality
0 - 1
Definition
A concept defining the context for this set of qualified values.
Comment
Binding
Strength
extensible
Description
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.context.CodeableConcept.coding
Id
CodeableConcept.coding
Type
Cardinality
0 - *
Definition
A reference to a code defined by a terminology system.
Comment
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.
Requirements
Allows for alternative encodings within a code system, and translations to other code systems.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.context.CodeableConcept.coding.Coding.system
Id
Coding.system
Type
Cardinality
0 - 1
Definition
The identification of the code system that defines the meaning of the symbol in the code.
Comment
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.
Requirements
Need to be unambiguous about the source of the definition of the symbol.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.context.CodeableConcept.coding.Coding.version
Id
Coding.version
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.context.CodeableConcept.coding.Coding.code
Id
Coding.code
Type
Cardinality
0 - 1
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).
Comment
Requirements
Need to refer to a particular code in the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.qualifiedValue.context.CodeableConcept.coding.Coding.display
Id
Coding.display
Type
Cardinality
0 - 1
Definition
A representation of the meaning of the code in the system, following the rules of the system.
Comment
Requirements
Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.qualifiedValue.context.CodeableConcept.coding.Coding.userSelected
Id
Coding.userSelected
Type
Cardinality
0 - 1
Definition
Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.appliesTo
Id
ObservationDefinition.qualifiedValue.appliesTo
Type
Cardinality
0 - *
Definition
The target population this set of qualified values applies to.
Comment
If this element is not present then the global population is assumed.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.appliesTo.CodeableConcept.coding
Id
CodeableConcept.coding
Type
Cardinality
0 - *
Definition
A reference to a code defined by a terminology system.
Comment
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.
Requirements
Allows for alternative encodings within a code system, and translations to other code systems.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.appliesTo.CodeableConcept.coding.Coding.system
Id
Coding.system
Type
Cardinality
0 - 1
Definition
The identification of the code system that defines the meaning of the symbol in the code.
Comment
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.
Requirements
Need to be unambiguous about the source of the definition of the symbol.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.appliesTo.CodeableConcept.coding.Coding.version
Id
Coding.version
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.appliesTo.CodeableConcept.coding.Coding.code
Id
Coding.code
Type
Cardinality
0 - 1
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).
Comment
Requirements
Need to refer to a particular code in the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.qualifiedValue.appliesTo.CodeableConcept.coding.Coding.display
Id
Coding.display
Type
Cardinality
0 - 1
Definition
A representation of the meaning of the code in the system, following the rules of the system.
Comment
Requirements
Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.qualifiedValue.appliesTo.CodeableConcept.coding.Coding.userSelected
Id
Coding.userSelected
Type
Cardinality
0 - 1
Definition
Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.gender
Id
ObservationDefinition.qualifiedValue.gender
Type
Cardinality
0 - 1
Definition
The gender this set of qualified values applies to.
Comment
Binding
Strength
required
Description
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.age
Id
ObservationDefinition.qualifiedValue.age
Type
Cardinality
0 - 1
Definition
The age range this set of qualified values applies to.
Comment
Some analytes vary greatly over age.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.age.Range.low
Id
Range.low
Type
Cardinality
0 - 1
Definition
The low limit. The boundary is inclusive.
Comment
If the low element is missing, the low boundary is not known.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
rng-2
Path
ObservationDefinition.qualifiedValue.age.Range.low.Quantity.value
Id
Quantity.value
Type
Cardinality
0 - 1
Definition
The value of the measured amount. The value includes an implicit precision in the presentation of the value.
Comment
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).
Requirements
Precision is handled implicitly in almost all cases of measurement.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.age.Range.low.Quantity.comparator
Id
Quantity.comparator
Type
Cardinality
0 - 1
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.
Comment
Requirements
Need a framework for handling measures where the value is <5ug/L or >400mg/L due to the limitations of measuring methodology.
Binding
Strength
required
Description
How the Quantity should be understood and represented.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.age.Range.low.Quantity.unit
Id
Quantity.unit
Type
Cardinality
0 - 1
Definition
A human-readable form of the unit.
Comment
Requirements
There are many representations for units of measure and in many contexts, particular representations are fixed and required. I.e. mcg for micrograms.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.age.Range.low.Quantity.system
Id
Quantity.system
Type
Cardinality
0 - 1
Definition
The identification of the system that provides the coded form of the unit.
Comment
Requirements
Need to know the system that defines the coded form of the unit.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
qty-3
Path
ObservationDefinition.qualifiedValue.age.Range.low.Quantity.code
Id
Quantity.code
Type
Cardinality
0 - 1
Definition
A computer processable form of the unit in some unit representation system.
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
qty-3
Path
ObservationDefinition.qualifiedValue.age.Range.high
Id
Range.high
Type
Cardinality
0 - 1
Definition
The high limit. The boundary is inclusive.
Comment
If the high element is missing, the high boundary is not known.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
rng-2
Path
ObservationDefinition.qualifiedValue.age.Range.high.Quantity.value
Id
Quantity.value
Type
Cardinality
0 - 1
Definition
The value of the measured amount. The value includes an implicit precision in the presentation of the value.
Comment
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).
Requirements
Precision is handled implicitly in almost all cases of measurement.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.age.Range.high.Quantity.comparator
Id
Quantity.comparator
Type
Cardinality
0 - 1
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.
Comment
Requirements
Need a framework for handling measures where the value is <5ug/L or >400mg/L due to the limitations of measuring methodology.
Binding
Strength
required
Description
How the Quantity should be understood and represented.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.age.Range.high.Quantity.unit
Id
Quantity.unit
Type
Cardinality
0 - 1
Definition
A human-readable form of the unit.
Comment
Requirements
There are many representations for units of measure and in many contexts, particular representations are fixed and required. I.e. mcg for micrograms.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.age.Range.high.Quantity.system
Id
Quantity.system
Type
Cardinality
0 - 1
Definition
The identification of the system that provides the coded form of the unit.
Comment
Requirements
Need to know the system that defines the coded form of the unit.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
qty-3
Path
ObservationDefinition.qualifiedValue.age.Range.high.Quantity.code
Id
Quantity.code
Type
Cardinality
0 - 1
Definition
A computer processable form of the unit in some unit representation system.
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
qty-3
Path
ObservationDefinition.qualifiedValue.gestationalAge
Id
ObservationDefinition.qualifiedValue.gestationalAge
Type
Cardinality
0 - 1
Definition
The gestational age this set of qualified values applies to.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.gestationalAge.Range.low
Id
Range.low
Type
Cardinality
0 - 1
Definition
The low limit. The boundary is inclusive.
Comment
If the low element is missing, the low boundary is not known.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
rng-2
Path
ObservationDefinition.qualifiedValue.gestationalAge.Range.low.Quantity.value
Id
Quantity.value
Type
Cardinality
0 - 1
Definition
The value of the measured amount. The value includes an implicit precision in the presentation of the value.
Comment
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).
Requirements
Precision is handled implicitly in almost all cases of measurement.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.gestationalAge.Range.low.Quantity.comparator
Id
Quantity.comparator
Type
Cardinality
0 - 1
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.
Comment
Requirements
Need a framework for handling measures where the value is <5ug/L or >400mg/L due to the limitations of measuring methodology.
Binding
Strength
required
Description
How the Quantity should be understood and represented.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.gestationalAge.Range.low.Quantity.unit
Id
Quantity.unit
Type
Cardinality
0 - 1
Definition
A human-readable form of the unit.
Comment
Requirements
There are many representations for units of measure and in many contexts, particular representations are fixed and required. I.e. mcg for micrograms.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.gestationalAge.Range.low.Quantity.system
Id
Quantity.system
Type
Cardinality
0 - 1
Definition
The identification of the system that provides the coded form of the unit.
Comment
Requirements
Need to know the system that defines the coded form of the unit.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
qty-3
Path
ObservationDefinition.qualifiedValue.gestationalAge.Range.low.Quantity.code
Id
Quantity.code
Type
Cardinality
0 - 1
Definition
A computer processable form of the unit in some unit representation system.
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
qty-3
Path
ObservationDefinition.qualifiedValue.gestationalAge.Range.high
Id
Range.high
Type
Cardinality
0 - 1
Definition
The high limit. The boundary is inclusive.
Comment
If the high element is missing, the high boundary is not known.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
rng-2
Path
ObservationDefinition.qualifiedValue.gestationalAge.Range.high.Quantity.value
Id
Quantity.value
Type
Cardinality
0 - 1
Definition
The value of the measured amount. The value includes an implicit precision in the presentation of the value.
Comment
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).
Requirements
Precision is handled implicitly in almost all cases of measurement.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.gestationalAge.Range.high.Quantity.comparator
Id
Quantity.comparator
Type
Cardinality
0 - 1
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.
Comment
Requirements
Need a framework for handling measures where the value is <5ug/L or >400mg/L due to the limitations of measuring methodology.
Binding
Strength
required
Description
How the Quantity should be understood and represented.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.gestationalAge.Range.high.Quantity.unit
Id
Quantity.unit
Type
Cardinality
0 - 1
Definition
A human-readable form of the unit.
Comment
Requirements
There are many representations for units of measure and in many contexts, particular representations are fixed and required. I.e. mcg for micrograms.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.gestationalAge.Range.high.Quantity.system
Id
Quantity.system
Type
Cardinality
0 - 1
Definition
The identification of the system that provides the coded form of the unit.
Comment
Requirements
Need to know the system that defines the coded form of the unit.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
qty-3
Path
ObservationDefinition.qualifiedValue.gestationalAge.Range.high.Quantity.code
Id
Quantity.code
Type
Cardinality
0 - 1
Definition
A computer processable form of the unit in some unit representation system.
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
qty-3
Path
ObservationDefinition.qualifiedValue.condition
Id
ObservationDefinition.qualifiedValue.condition
Type
Cardinality
0 - 1
Definition
Text based condition for which the the set of qualified values is valid.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.rangeCategory
Id
ObservationDefinition.qualifiedValue.rangeCategory
Type
Cardinality
0 - 1
Definition
The category of range of values for continuous or ordinal observations that match the criteria of this set of qualified values.
Comment
Binding
Strength
required
Description
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.range
Id
ObservationDefinition.qualifiedValue.range
Type
Cardinality
0 - 1
Definition
The range of values defined for continuous or ordinal observations that match the criteria of this set of qualified values.
Comment
Requirements
The unit may be not relevant for ordinal values. In case it is there, it is the same as ObservationDefinition.unit.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.range.Range.low
Id
Range.low
Type
Cardinality
0 - 1
Definition
The low limit. The boundary is inclusive.
Comment
If the low element is missing, the low boundary is not known.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
rng-2
Path
ObservationDefinition.qualifiedValue.range.Range.low.Quantity.value
Id
Quantity.value
Type
Cardinality
0 - 1
Definition
The value of the measured amount. The value includes an implicit precision in the presentation of the value.
Comment
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).
Requirements
Precision is handled implicitly in almost all cases of measurement.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.range.Range.low.Quantity.comparator
Id
Quantity.comparator
Type
Cardinality
0 - 1
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.
Comment
Requirements
Need a framework for handling measures where the value is <5ug/L or >400mg/L due to the limitations of measuring methodology.
Binding
Strength
required
Description
How the Quantity should be understood and represented.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.range.Range.low.Quantity.unit
Id
Quantity.unit
Type
Cardinality
0 - 1
Definition
A human-readable form of the unit.
Comment
Requirements
There are many representations for units of measure and in many contexts, particular representations are fixed and required. I.e. mcg for micrograms.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.range.Range.low.Quantity.system
Id
Quantity.system
Type
Cardinality
0 - 1
Definition
The identification of the system that provides the coded form of the unit.
Comment
Requirements
Need to know the system that defines the coded form of the unit.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
qty-3
Path
ObservationDefinition.qualifiedValue.range.Range.low.Quantity.code
Id
Quantity.code
Type
Cardinality
0 - 1
Definition
A computer processable form of the unit in some unit representation system.
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
qty-3
Path
ObservationDefinition.qualifiedValue.range.Range.high
Id
Range.high
Type
Cardinality
0 - 1
Definition
The high limit. The boundary is inclusive.
Comment
If the high element is missing, the high boundary is not known.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
rng-2
Path
ObservationDefinition.qualifiedValue.range.Range.high.Quantity.value
Id
Quantity.value
Type
Cardinality
0 - 1
Definition
The value of the measured amount. The value includes an implicit precision in the presentation of the value.
Comment
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).
Requirements
Precision is handled implicitly in almost all cases of measurement.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.range.Range.high.Quantity.comparator
Id
Quantity.comparator
Type
Cardinality
0 - 1
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.
Comment
Requirements
Need a framework for handling measures where the value is <5ug/L or >400mg/L due to the limitations of measuring methodology.
Binding
Strength
required
Description
How the Quantity should be understood and represented.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.range.Range.high.Quantity.unit
Id
Quantity.unit
Type
Cardinality
0 - 1
Definition
A human-readable form of the unit.
Comment
Requirements
There are many representations for units of measure and in many contexts, particular representations are fixed and required. I.e. mcg for micrograms.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.qualifiedValue.range.Range.high.Quantity.system
Id
Quantity.system
Type
Cardinality
0 - 1
Definition
The identification of the system that provides the coded form of the unit.
Comment
Requirements
Need to know the system that defines the coded form of the unit.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
qty-3
Path
ObservationDefinition.qualifiedValue.range.Range.high.Quantity.code
Id
Quantity.code
Type
Cardinality
0 - 1
Definition
A computer processable form of the unit in some unit representation system.
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
qty-3
validCodedValueSet
Value set of valid coded values as part of this set of qualified values
Path
ObservationDefinition.qualifiedValue.validCodedValueSet
Id
ObservationDefinition.qualifiedValue.validCodedValueSet
Type
Cardinality
0 - 1
Definition
The set of valid coded results for qualitative observations that match the criteria of this set of qualified values.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
normalCodedValueSet
Value set of normal coded values as part of this set of qualified values
Path
ObservationDefinition.qualifiedValue.normalCodedValueSet
Id
ObservationDefinition.qualifiedValue.normalCodedValueSet
Type
Cardinality
0 - 1
Definition
The set of normal coded results for qualitative observations that match the criteria of this set of qualified values.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
abnormalCodedValueSet
Value set of abnormal coded values as part of this set of qualified values
Path
ObservationDefinition.qualifiedValue.abnormalCodedValueSet
Id
ObservationDefinition.qualifiedValue.abnormalCodedValueSet
Type
Cardinality
0 - 1
Definition
The set of abnormal coded results for qualitative observations that match the criteria of this set of qualified values.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
criticalCodedValueSet
Value set of critical coded values as part of this set of qualified values
Path
ObservationDefinition.qualifiedValue.criticalCodedValueSet
Id
ObservationDefinition.qualifiedValue.criticalCodedValueSet
Type
Cardinality
0 - 1
Definition
The set of critical coded results for qualitative observations that match the criteria of this set of qualified values.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.hasMember
Id
ObservationDefinition.hasMember
Type
Cardinality
0 - *
Definition
This ObservationDefinition defines 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.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.hasMember.Reference.reference
Id
Reference.reference
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
ref-1
Path
ObservationDefinition.hasMember.Reference.type
Id
Reference.type
Type
Cardinality
0 - 1
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).
Comment
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 known RESTful URL) or by resolving the target of the reference.
Binding
Strength
extensible
Description
Aa resource (or, for logical models, the URI of the logical model).
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.hasMember.Reference.identifier
Id
Reference.identifier
Type
Cardinality
0 - 1
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.
Comment
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).
This element only allows for a single identifier. In the case where additional identifers are required, use the [http://hl7.org/fhir/StructureDefinition/additionalIdentifier](http://hl7.org/fhir/extensions/StructureDefinition-additionalIdentifier.html) extension.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
Path
ObservationDefinition.hasMember.Reference.identifier.Identifier.use
Id
Identifier.use
Type
Cardinality
0 - 1
Definition
The purpose of this identifier.
Comment
Applications can assume that an identifier is permanent unless it explicitly says that it is temporary.
Requirements
Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers.
Binding
Strength
required
Description
Identifies the purpose for this identifier, if known .
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.hasMember.Reference.identifier.Identifier.type
Id
Identifier.type
Type
Cardinality
0 - 1
Definition
A coded type for the identifier that can be used to determine which identifier to use for a specific purpose.
Comment
This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type.
Requirements
Allows users to make use of identifiers when the identifier system is not known.
Binding
Strength
extensible
Description
A coded type for an identifier that can be used to determine which identifier to use for a specific purpose.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.hasMember.Reference.identifier.Identifier.type.CodeableConcept.coding
Id
CodeableConcept.coding
Type
Cardinality
0 - *
Definition
A reference to a code defined by a terminology system.
Comment
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.
Requirements
Allows for alternative encodings within a code system, and translations to other code systems.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.hasMember.Reference.identifier.Identifier.system
Id
Identifier.system
Type
Cardinality
0 - 1
Definition
Establishes the namespace for the value - that is, an absolute URL that describes a set values that are unique.
Comment
Identifier.system is always case sensitive.
Requirements
There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.hasMember.Reference.identifier.Identifier.value
Id
Identifier.value
Type
Cardinality
0 - 1
Definition
The portion of the identifier typically relevant to the user and which is unique within the context of the system.
Comment
If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the [http://hl7.org/fhir/StructureDefinition/rendered-value](http://hl7.org/fhir/extensions/StructureDefinition-rendered-value.html)). Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ident-1
Path
ObservationDefinition.hasMember.Reference.identifier.Identifier.period
Id
Identifier.period
Type
Cardinality
0 - 1
Definition
Time period during which identifier is/was valid for use.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.hasMember.Reference.identifier.Identifier.period.Period.start
Id
Period.start
Type
Cardinality
0 - 1
Definition
The start of the period. The boundary is inclusive.
Comment
If the low element is missing, the meaning is that the low boundary is not known.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
per-1
Path
ObservationDefinition.hasMember.Reference.identifier.Identifier.period.Period.end
Id
Period.end
Type
Cardinality
0 - 1
Definition
The end of the period. If the end of the period is missing, it means no end was known or planned at the time the instance was created. The start may be in the past, and the end date in the future, which means that period is expected/planned to end at that time.
Comment
The end value includes any matching date/time. i.e. 2012-02-03T10:00:00 is in a period that has an end value of 2012-02-03.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
per-1
Path
ObservationDefinition.hasMember.Reference.identifier.Identifier.assigner
Id
Identifier.assigner
Type
Cardinality
0 - 1
Definition
Organization that issued/manages the identifier.
Comment
The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.hasMember.Reference.identifier.Identifier.assigner.Reference.reference
Id
Reference.reference
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
ref-1
Path
ObservationDefinition.hasMember.Reference.identifier.Identifier.assigner.Reference.type
Id
Reference.type
Type
Cardinality
0 - 1
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).
Comment
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 known RESTful URL) or by resolving the target of the reference.
Binding
Strength
extensible
Description
Aa resource (or, for logical models, the URI of the logical model).
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.hasMember.Reference.identifier.Identifier.assigner.Reference.identifier
Id
Reference.identifier
Type
Cardinality
0 - 1
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.
Comment
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).
This element only allows for a single identifier. In the case where additional identifers are required, use the [http://hl7.org/fhir/StructureDefinition/additionalIdentifier](http://hl7.org/fhir/extensions/StructureDefinition-additionalIdentifier.html) extension.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
Path
ObservationDefinition.hasMember.Reference.identifier.Identifier.assigner.Reference.display
Id
Reference.display
Type
Cardinality
0 - 1
Definition
Plain text narrative that identifies the resource in addition to the resource reference.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
Path
ObservationDefinition.hasMember.Reference.display
Id
Reference.display
Type
Cardinality
0 - 1
Definition
Plain text narrative that identifies the resource in addition to the resource reference.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
ref-2
Path
ObservationDefinition.component
Id
ObservationDefinition.component
Type
Cardinality
0 - *
Definition
Some observations have multiple component observations, expressed as separate code value pairs.
Comment
Requirements
Component observations share the same attributes as the primary observation and are always treated as a part of it (they are not separable).
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
obd-1 [error]
If permittedUnit exists, then permittedDataType=Quantity must exist.
Path
ObservationDefinition.component.code
Id
ObservationDefinition.component.code
Type
Cardinality
1 - 1
Definition
Describes what will be observed.
Comment
Binding
Strength
example
Description
Codes identifying names of simple observations.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.component.code.CodeableConcept.coding
Id
CodeableConcept.coding
Type
Cardinality
0 - *
Definition
A reference to a code defined by a terminology system.
Comment
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.
Requirements
Allows for alternative encodings within a code system, and translations to other code systems.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.component.code.CodeableConcept.coding.Coding.system
Id
Coding.system
Type
Cardinality
0 - 1
Definition
The identification of the code system that defines the meaning of the symbol in the code.
Comment
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.
Requirements
Need to be unambiguous about the source of the definition of the symbol.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.component.code.CodeableConcept.coding.Coding.version
Id
Coding.version
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.component.code.CodeableConcept.coding.Coding.code
Id
Coding.code
Type
Cardinality
0 - 1
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).
Comment
Requirements
Need to refer to a particular code in the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.component.code.CodeableConcept.coding.Coding.display
Id
Coding.display
Type
Cardinality
0 - 1
Definition
A representation of the meaning of the code in the system, following the rules of the system.
Comment
Requirements
Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.component.code.CodeableConcept.coding.Coding.userSelected
Id
Coding.userSelected
Type
Cardinality
0 - 1
Definition
Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
permittedDataType
Quantity | CodeableConcept | string | boolean | integer | Range | Ratio | SampledData | time | dateTime | Period
Path
ObservationDefinition.component.permittedDataType
Id
ObservationDefinition.component.permittedDataType
Type
Cardinality
0 - *
Definition
The data types allowed for the value element of the instance of this component observations.
Comment
Binding
Strength
required
Description
Permitted data type for observation value.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
obd-1
Path
ObservationDefinition.component.permittedUnit
Id
ObservationDefinition.component.permittedUnit
Type
Cardinality
0 - *
Definition
Units allowed for the valueQuantity element in the instance observations conforming to this ObservationDefinition.
Comment
Binding
Strength
preferred
Description
Codes identifying units of measure.
ValueSet
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
obd-1
Path
ObservationDefinition.component.permittedUnit.Coding.system
Id
Coding.system
Type
Cardinality
0 - 1
Definition
The identification of the code system that defines the meaning of the symbol in the code.
Comment
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.
Requirements
Need to be unambiguous about the source of the definition of the symbol.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.component.permittedUnit.Coding.version
Id
Coding.version
Type
Cardinality
0 - 1
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.
Comment
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Path
ObservationDefinition.component.permittedUnit.Coding.code
Id
Coding.code
Type
Cardinality
0 - 1
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).
Comment
Requirements
Need to refer to a particular code in the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.component.permittedUnit.Coding.display
Id
Coding.display
Type
Cardinality
0 - 1
Definition
A representation of the meaning of the code in the system, following the rules of the system.
Comment
Requirements
Need to be able to carry a human-readable meaning of the code for readers that do not know the system.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
Condition
cod-1
Path
ObservationDefinition.component.permittedUnit.Coding.userSelected
Id
Coding.userSelected
Type
Cardinality
0 - 1
Definition
Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays).
Comment
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.
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.
Constraint
ele-1 [error]
All FHIR elements must have a @value or children
qualifiedValue
Set of qualified values for observation results
Path
ObservationDefinition.component.qualifiedValue
Id
ObservationDefinition.component.qualifiedValue
Type
Cardinality
0 - *
Definition
A set of qualified values associated with a context and a set of conditions - provides a range for quantitative and ordinal observations and a collection of value sets for qualitative observations.
Comment
Constraint
ele-1 [error]
All FHIR elements must have a @value or children