FHIR IG Statistics: StructureDefinition/sdc-questionnaire-candidateExpression
| Package | hl7.fhir.uv.sdc |
| Resource Type | StructureDefinition |
| Id | sdc-questionnaire-candidateExpression |
| FHIR Version | R4 |
| Source | http://hl7.org/fhir/uv/sdc/https://build.fhir.org/ig/HL7/sdc/StructureDefinition-sdc-questionnaire-candidateExpression.html |
| URL | http://hl7.org/fhir/uv/sdc/StructureDefinition/sdc-questionnaire-candidateExpression |
| Version | 4.0.0-ballot |
| Status | active |
| Date | 2025-07-14T18:38:59+00:00 |
| Name | CandidateExpressionExtension |
| Title | Candidate Answers Expression |
| Realm | uv |
| Authority | hl7 |
| Description | A FHIRPath or CQL expression, or FHIR Query that resolves to a list of candidate answers for the question item or that establishes context for a group item. The user may select from among the candidates to choose answers for the question. |
| Type | Extension |
| Kind | complex-type |
Resources that use this resource
Resources that this resource uses
No resources found
Examples of Use for Extension
Narrative
Note: links and images are rebased to the (stated) source
Source
{
"resourceType": "StructureDefinition",
"id": "sdc-questionnaire-candidateExpression",
"text": {
"status": "extensions",
"div": "<!-- snip (see above) -->"
},
"extension": [
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-wg",
"valueCode": "fhir"
},
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fmm",
"valueInteger": 4,
"_valueInteger": {
"extension": [
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-conformance-derivedFrom",
"valueCanonical": "http://hl7.org/fhir/uv/sdc/ImplementationGuide/hl7.fhir.uv.sdc"
}
]
}
},
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-standards-status",
"valueCode": "trial-use",
"_valueCode": {
"extension": [
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-conformance-derivedFrom",
"valueCanonical": "http://hl7.org/fhir/uv/sdc/ImplementationGuide/hl7.fhir.uv.sdc"
}
]
}
}
],
"url": "http://hl7.org/fhir/uv/sdc/StructureDefinition/sdc-questionnaire-candidateExpression",
"identifier": [
{
"system": "urn:ietf:rfc:3986",
"value": "urn:oid:2.16.840.1.113883.4.642.40.17.42.18"
}
],
"version": "4.0.0-ballot",
"name": "CandidateExpressionExtension",
"title": "Candidate Answers Expression",
"status": "active",
"date": "2025-07-14T18:38:59+00:00",
"publisher": "HL7 International / FHIR Infrastructure",
"contact": [
{
"name": "HL7 International / FHIR Infrastructure",
"telecom": [
{
"system": "url",
"value": "http://www.hl7.org/Special/committees/fiwg"
}
]
},
{
"telecom": [
{
"system": "url",
"value": "http://www.hl7.org/Special/committees/fiwg"
}
]
}
],
"description": "A FHIRPath or CQL expression, or FHIR Query that resolves to a list of candidate answers for the question item or that establishes context for a group item. The user may select from among the candidates to choose answers for the question.",
"jurisdiction": [
{
"coding": [
{
"system": "http://unstats.un.org/unsd/methods/m49/m49.htm",
"code": "001",
"display": "World"
}
]
}
],
"fhirVersion": "4.0.1",
"mapping": [
{
"identity": "rim",
"uri": "http://hl7.org/v3",
"name": "RIM Mapping"
}
],
"kind": "complex-type",
"abstract": false,
"context": [
{
"type": "element",
"expression": "Questionnaire.item"
},
{
"type": "element",
"expression": "ElementDefinition"
}
],
"type": "Extension",
"baseDefinition": "http://hl7.org/fhir/StructureDefinition/Extension",
"derivation": "constraint",
"snapshot": {
"extension": [
{
"url": "http://hl7.org/fhir/tools/StructureDefinition/snapshot-base-version",
"valueString": "4.0.1"
}
],
"element": [
{
"id": "Extension",
"path": "Extension",
"short": "Expression for possible answers",
"definition": "A FHIRPath or CQL expression, or FHIR Query that resolves to a list of candidate answers for the question item or that establishes context for a group item. The user may select from among the candidates to choose answers for the question.",
"comment": "The results of the expression must correspond to the item type of the question the element appears on or must correspond to a resource, backbone element or complex data type for a group item. Resources are considered a match for the Reference item type. Quantity can be a match for decimal and integer items so long as a questionnaire-unit extension is present. If the expression returns coded data, it **SHALL* return the information as either code or Coding, not CodeableConcept. If the expression returns elements of type 'code', when the user selects one or more candidates, the code will be matched against the allowed Codings (from answerValueSet, answerOptions, or answerExpresssion). In this case, it is an error if there is more than one Coding with the same code.",
"min": 0,
"max": "1",
"base": {
"path": "Extension",
"min": 0,
"max": "*"
},
"condition": [
"ele-1"
],
"constraint": [
{
"key": "ele-1",
"severity": "error",
"human": "All FHIR elements must have a @value or children",
"expression": "hasValue() or (children().count() > id.count())",
"xpath": "@value|f:*|h:div",
"source": "http://hl7.org/fhir/StructureDefinition/Element"
},
{
"key": "ext-1",
"severity": "error",
"human": "Must have either extensions or value[x], not both",
"expression": "extension.exists() != value.exists()",
"xpath": "exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')])",
"source": "http://hl7.org/fhir/StructureDefinition/Extension"
}
],
"isModifier": false
},
{
"id": "Extension.id",
"path": "Extension.id",
"representation": [
"xmlAttr"
],
"short": "Unique id for inter-element referencing",
"definition": "Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.",
"min": 0,
"max": "1",
"base": {
"path": "Element.id",
"min": 0,
"max": "1"
},
"type": [
{
"extension": [
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
"valueUrl": "string"
}
],
"code": "http://hl7.org/fhirpath/System.String"
}
],
"isModifier": false,
"isSummary": false,
"mapping": [
{
"identity": "rim",
"map": "n/a"
}
]
},
{
"id": "Extension.extension",
"path": "Extension.extension",
"slicing": {
"discriminator": [
{
"type": "value",
"path": "url"
}
],
"description": "Extensions are always sliced by (at least) url",
"rules": "open"
},
"short": "Extension",
"definition": "An Extension",
"min": 0,
"max": "0",
"base": {
"path": "Element.extension",
"min": 0,
"max": "*"
},
"type": [
{
"code": "Extension"
}
],
"constraint": [
{
"key": "ele-1",
"severity": "error",
"human": "All FHIR elements must have a @value or children",
"expression": "hasValue() or (children().count() > id.count())",
"xpath": "@value|f:*|h:div",
"source": "http://hl7.org/fhir/StructureDefinition/Element"
},
{
"key": "ext-1",
"severity": "error",
"human": "Must have either extensions or value[x], not both",
"expression": "extension.exists() != value.exists()",
"xpath": "exists(f:extension)!=exists(f:*[starts-with(local-name(.), \"value\")])",
"source": "http://hl7.org/fhir/StructureDefinition/Extension"
}
],
"isModifier": false,
"isSummary": false
},
{
"id": "Extension.url",
"path": "Extension.url",
"representation": [
"xmlAttr"
],
"short": "identifies the meaning of the extension",
"definition": "Source of the definition for the extension code - a logical name or a URL.",
"comment": "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.",
"min": 1,
"max": "1",
"base": {
"path": "Extension.url",
"min": 1,
"max": "1"
},
"type": [
{
"extension": [
{
"url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type",
"valueUrl": "uri"
}
],
"code": "http://hl7.org/fhirpath/System.String"
}
],
"fixedUri": "http://hl7.org/fhir/uv/sdc/StructureDefinition/sdc-questionnaire-candidateExpression",
"isModifier": false,
"isSummary": false,
"mapping": [
{
"identity": "rim",
"map": "N/A"
}
]
},
{
"id": "Extension.value[x]",
"path": "Extension.value[x]",
"short": "Value of extension",
"definition": "Value of extension - must be one of a constrained set of the data types (see [Extensibility](http://hl7.org/fhir/R4/extensibility.html) for a list).",
"min": 0,
"max": "1",
"base": {
"path": "Extension.value[x]",
"min": 0,
"max": "1"
},
"type": [
{
"code": "Expression"
}
],
"constraint": [
{
"key": "ele-1",
"severity": "error",
"human": "All FHIR elements must have a @value or children",
"expression": "hasValue() or (children().count() > id.count())",
"xpath": "@value|f:*|h:div",
"source": "http://hl7.org/fhir/StructureDefinition/Element"
}
],
"isModifier": false,
"isSummary": false,
"mapping": [
{
"identity": "rim",
"map": "N/A"
}
]
}
]
},
"differential": {
"element": [
{
"id": "Extension",
"path": "Extension",
"short": "Expression for possible answers",
"definition": "A FHIRPath or CQL expression, or FHIR Query that resolves to a list of candidate answers for the question item or that establishes context for a group item. The user may select from among the candidates to choose answers for the question.",
"comment": "The results of the expression must correspond to the item type of the question the element appears on or must correspond to a resource, backbone element or complex data type for a group item. Resources are considered a match for the Reference item type. Quantity can be a match for decimal and integer items so long as a questionnaire-unit extension is present. If the expression returns coded data, it **SHALL* return the information as either code or Coding, not CodeableConcept. If the expression returns elements of type 'code', when the user selects one or more candidates, the code will be matched against the allowed Codings (from answerValueSet, answerOptions, or answerExpresssion). In this case, it is an error if there is more than one Coding with the same code.",
"max": "1"
},
{
"id": "Extension.extension",
"path": "Extension.extension",
"max": "0"
},
{
"id": "Extension.url",
"path": "Extension.url",
"fixedUri": "http://hl7.org/fhir/uv/sdc/StructureDefinition/sdc-questionnaire-candidateExpression"
},
{
"id": "Extension.value[x]",
"path": "Extension.value[x]",
"type": [
{
"code": "Expression"
}
]
}
]
}
}
Extension 
extension 
value[x] 
FHIR