<StructureDefinition xmlns="http://hl7.org/fhir">
  <id value="ChangeEventExtension" />
  <meta>
    <lastUpdated value="2019-06-08T09:25:12.039-04:00" />
  </meta>
  <url value="http://VA.gov/FHIR/StructureDefinition/Extension/ChangeEventExtension" />
  <name value="ChangeEventExtension" />
  <status value="draft" />
  <date value="2019-06-08T09:16:11.759-04:00" />
  <description value="Extension to support inclusion of ChangeEvent profile on Reference" />
  <fhirVersion value="1.0.2" />
  <kind value="datatype" />
  <constrainedType value="Extension" />
  <abstract value="false" />
  <contextType value="resource" />
  <context value="MedicationAdministration" />
  <context value="MedicationOrder" />
  <context value="Condition" />
  <base value="http://hl7.org/fhir/StructureDefinition/Extension" />
  <differential>
    <element>
      <path value="Extension" />
    </element>
    <element>
      <path value="Extension.url" />
      <fixedUri value="StructureDefinition/ChangeEventExtension" />
    </element>
    <element>
      <path value="Extension.valueReference" />
      <type>
        <code value="Reference" />
      </type>
      <constraint>
        <key value="uniqueidentifierforchangeeventconstraint" />
        <requirements value="Referenced AuditEvent must be conform to ChangeEvent profile" />
        <severity value="error" />
        <human value="Referenced AuditEvent must be conform to ChangeEvent profile" />
        <xpath value="Reference.reference.ChangeEvent" />
      </constraint>
    </element>
  </differential>
</StructureDefinition>