description: For requisitions this extension is used to convey the ServiceRequest.requisition identifier in the message header. package_name: ca.on.oh derivation: constraint name: ReferralIdentifier type: Extension elements: url: pattern: {type: Uri, value: 'http://fhir.infoway-inforoute.ca/io/CA-eReC/StructureDefinition/Referral-Identifier-EXT'} index: 0 value: choices: [valueIdentifier] index: 2 valueIdentifier: {type: Identifier, choiceOf: value, index: 3} package_version: ereferral-econsult-0.12.0-projectathon1.0.2 class: extension kind: complex-type url: http://fhir.infoway-inforoute.ca/io/CA-eReC/StructureDefinition/Referral-Identifier-EXT base: http://hl7.org/fhir/StructureDefinition/Extension version: 0.10.1 required: [valueIdentifier, value]