<StructureDefinition xmlns="http://hl7.org/fhir">
  <meta>
    <lastUpdated value="2018-09-29T16:12:56.185+00:00" />
  </meta>
  <url value="http://example.org/fhir/StructureDefinition/TestTCBResearch" />
  <name value="TestTCBResearch" />
  <status value="draft" />
  <date value="2018-09-29T16:12:55.9767217+00:00" />
  <fhirVersion value="3.0.1" />
  <kind value="resource" />
  <abstract value="false" />
  <type value="ResearchStudy" />
  <baseDefinition value="http://hl7.org/fhir/StructureDefinition/ResearchStudy" />
  <derivation value="constraint" />
  <differential>
    <element id="ResearchStudy.period">
      <path value="ResearchStudy.period" />
      <min value="1" />
    </element>
    <element id="ResearchStudy.period.start">
      <path value="ResearchStudy.period.start" />
      <min value="1" />
    </element>
    <element id="ResearchStudy.period.end">
      <path value="ResearchStudy.period.end" />
      <min value="1" />
    </element>
  </differential>
</StructureDefinition>