description: Indicates the terminology server(s) that are known to be capable of returning and potentially expanding the value set(s) associated with the whole questionnaire or a particular group or question within the questionnaire (depending on where the extension appears). If a full URL is not provided AND the requested query is a terminology operation (e.g. $lookup or $expand) the client SHOULD execute the operation against the preferredTerminologyServer rather than the local repository. package_name: ca.on.health.sadie derivation: constraint name: PreferredTerminologyServer type: Extension elements: url: type: uri pattern: {type: Uri, value: 'http://hl7.org/fhir/uv/sdc/StructureDefinition/sdc-questionnaire-preferredTerminologyServer'} index: 0 value: choices: [valueUrl] index: 2 valueUrl: {type: url, choiceOf: value, index: 3} package_version: 0.1.19-beta class: extension kind: complex-type url: http://hl7.org/fhir/uv/sdc/StructureDefinition/sdc-questionnaire-preferredTerminologyServer base: http://hl7.org/fhir/StructureDefinition/Extension version: 2.8.0