{
  "resourceType": "StructureDefinition",
  "id": "custom-questionnaire-response",
  "url": "https://simplifier.net/resqplus/StructureDefinition/custom-questionnaire-response",
  "name": "CustomQuestionnaireResponse",
  "status": "active",
  "description": "Custom profile for PHQ-9 QuestionnaireResponse",
  "fhirVersion": "4.0.1",
  "kind": "resource",
  "abstract": false,
  "type": "QuestionnaireResponse",
  "baseDefinition": "http://hl7.org/fhir/StructureDefinition/QuestionnaireResponse",
  "derivation": "constraint",
  "differential": {
    "element": [
      {
        "id": "QuestionnaireResponse.item.answer.valueCoding",
        "path": "QuestionnaireResponse.item.answer.valueCoding",
        "min": 1,
        "type": [
          {
            "code": "Coding"
          }
        ],
        "binding": {
          "strength": "required",
          "valueSet": "https://simplifier.net/resqplus/ValueSet/phq9-common-answers"
        }
      },
      {
        "id": "QuestionnaireResponse.item",
        "path": "QuestionnaireResponse.item",
        "min": 1,
        "constraint": [
          {
            "key": "obligatory-question",
            "severity": "error",
            "human": "A response is required for this question",
            "expression": "answer.exists()"
          }
        ]
      }
    ]
  }
}