description: A code representing the the type of specimen used for this observation. Should only be used if not implicit in the code found in `Observation.code`. package_name: rs/hl7.fhir.uv.extensions derivation: constraint name: ObsSpecimenCode type: Extension elements: extension: {index: 0} url: pattern: {type: uri, value: 'http://hl7.org/fhir/StructureDefinition/observation-specimenCode'} type: uri index: 1 value: choices: [valueCodeableConcept] index: 3 valueCodeableConcept: {type: CodeableConcept, choiceOf: value, index: 4} package_version: 5.1.0 extensions: {} class: extension kind: complex-type url: http://hl7.org/fhir/StructureDefinition/observation-specimenCode base: http://hl7.org/fhir/StructureDefinition/Extension version: 5.1.0 required: [value, valueCodeableConcept]