Extensions for Using Data Elements from FHIR STU3 in FHIR R4B
0.1.0 - STU
Extensions for Using Data Elements from FHIR STU3 in FHIR R4B
0.1.0 - STU
Extensions for Using Data Elements from FHIR STU3 in FHIR R4B - Downloaded Version null See the Directory of published versions
| Page standards status: Trial-use | Maturity Level: 0 |
Definitions for the ext-R3-Reference.identifier extension.
Guidance on how to interpret the contents of this table can be foundhere
| 0. Extension | |
| Definition | STU3: Optional Extension Element - found in all resources. |
| Short | STU3: identifier additional typesOptional Extensions Element |
| Comments | Element 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. |
| Control | 0..1* This element is affected by the following invariants: ele-1 |
| Is Modifier | false |
| Invariants | ele-1: All FHIR elements must have a @value or children unless an empty Parameters resource (hasValue() or (children().count() > id.count()) or $this is Parameters)ext-1: Must have either extensions or value[x], not both ( extension.exists() != value.exists())ele-1: All FHIR elements must have a @value or children unless an empty Parameters resource (hasValue() or (children().count() > id.count()) or $this is Parameters) ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists()) |
| 2. Extension.url | |
| Definition | Source of the definition for the extension code - a logical name or a URL. |
| Short | identifies the meaning of the extension |
| Comments | The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension. |
| Control | 1..1 |
| Type | uri |
| Is Modifier | false |
| XML Format | In the XML format, this property is represented as an attribute. |
| Summary | false |
| Fixed Value | http://hl7.org/fhir/3.0/StructureDefinition/extension-Reference.identifier |
| 4. Extension.value[x] | |
| Definition | An identifier for the other resource. This is used when there is no way to reference the other resource directly, either because the entity is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Value of extension - must be one of a constrained set of the data types (see Extensibility for a list). |
| Short | Logical reference, when literal reference is not knownValue of extension |
| Comments | When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. |
| Control | 0..1 |
| Type | Identifier, date, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, RatioRange, Coding, SampledData, id, positiveInt, Distance, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, CodeableConcept, ParameterDefinition, dateTime, code, string, Contributor, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, Reference, TriggerDefinition, Quantity, uri, url, Annotation, ContactDetail, boolean, Expression, CodeableReference, Signature, unsignedInt, time |
| [x] Note | SeeChoice of Data Typesfor further information about how to use [x] |
| Is Modifier | false |
| Summary | false |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) |
Guidance on how to interpret the contents of this table can be foundhere
| 0. Extension | |
| Definition | STU3: |
| Short | STU3: identifier additional types |
| Comments | Element 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. |
| Control | 0..1 |
| Is Modifier | false |
| 2. Extension.url | |
| Control | 1..1 |
| Fixed Value | http://hl7.org/fhir/3.0/StructureDefinition/extension-Reference.identifier |
| 4. Extension.value[x] | |
| Definition | An identifier for the other resource. This is used when there is no way to reference the other resource directly, either because the entity is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. |
| Short | Logical reference, when literal reference is not known |
| Comments | When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. |
| Control | 0..1 |
| Type | Identifier, date, Address, Attachment, integer, Count, DataRequirement, Dosage, uuid, RatioRange, Coding, SampledData, id, positiveInt, Distance, Period, Duration, canonical, Range, RelatedArtifact, base64Binary, UsageContext, Timing, decimal, CodeableConcept, ParameterDefinition, dateTime, code, string, Contributor, oid, instant, ContactPoint, HumanName, Money, markdown, Ratio, Age, Reference, TriggerDefinition, Quantity, uri, url, Annotation, ContactDetail, boolean, Expression, CodeableReference, Signature, unsignedInt, time |
| [x] Note | SeeChoice of Data Typesfor further information about how to use [x] |
Guidance on how to interpret the contents of this table can be foundhere
| 0. Extension | |
| Definition | STU3: |
| Short | STU3: identifier additional types |
| Comments | Element 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. |
| Control | 0..1 This element is affected by the following invariants: ele-1 |
| Is Modifier | false |
| Invariants | ele-1: All FHIR elements must have a @value or children unless an empty Parameters resource (hasValue() or (children().count() > id.count()) or $this is Parameters)ext-1: Must have either extensions or value[x], not both ( extension.exists() != value.exists()) |
| 2. Extension.id | |
| Definition | Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces. |
| Short | Unique id for inter-element referencing |
| Control | 0..1 |
| Type | id |
| Is Modifier | false |
| XML Format | In the XML format, this property is represented as an attribute. |
| Summary | false |
| 4. Extension.extension | |
| Definition | May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. |
| Short | Additional content defined by implementations |
| Comments | There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. |
| Control | 0..* |
| Type | Extension |
| Is Modifier | false |
| Summary | false |
| Alternate Names | extensions, user content |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))ext-1: Must have either extensions or value[x], not both ( extension.exists() != value.exists()) |
| Slicing | This element introduces a set of slices on Extension.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators: |
| 6. Extension.url | |
| Definition | Source of the definition for the extension code - a logical name or a URL. |
| Short | identifies the meaning of the extension |
| Comments | The definition may point directly to a computable or human-readable definition of the extensibility codes, or it may be a logical URI as declared in some other specification. The definition SHALL be a URI for the Structure Definition defining the extension. |
| Control | 1..1 |
| Type | uri |
| Is Modifier | false |
| XML Format | In the XML format, this property is represented as an attribute. |
| Summary | false |
| Fixed Value | http://hl7.org/fhir/3.0/StructureDefinition/extension-Reference.identifier |
| 8. Extension.value[x] | |
| Definition | An identifier for the other resource. This is used when there is no way to reference the other resource directly, either because the entity is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. |
| Short | Logical reference, when literal reference is not known |
| Comments | When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. |
| Control | 0..1 |
| Type | Identifier |
| [x] Note | SeeChoice of Data Typesfor further information about how to use [x] |
| Is Modifier | false |
| Summary | false |
| Invariants | ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count())) |
IG © 2025+ FHIR Infrastructure. Package hl7.fhir.uv.xver-r3.r4b#0.1.0 based on FHIR 4.3.0. Generated 2026-03-20
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