<SearchParameter xmlns="http://hl7.org/fhir">
  <id value="DocumentReference-subject" />
  <url value="http://hl7.org/fhir/SearchParameter/DocumentReference-subject" />
  <name value="subject" />
  <status value="draft" />
  <experimental value="false" />
  <date value="2017-04-19T07:44:43+10:00" />
  <publisher value="Health Level Seven International (Structured Documents)" />
  <contact>
    <telecom>
      <system value="url" />
      <value value="http://hl7.org/fhir" />
    </telecom>
  </contact>
  <contact>
    <telecom>
      <system value="url" />
      <value value="http://www.hl7.org/Special/committees/structure/index.cfm" />
    </telecom>
  </contact>
  <code value="subject" />
  <base value="DocumentReference" />
  <type value="reference" />
  <description value="Who/what is the subject of the document" />
  <expression value="DocumentReference.subject" />
  <xpath value="f:DocumentReference/f:subject" />
  <xpathUsage value="normal" />
  <target value="Practitioner" />
  <target value="Group" />
  <target value="Device" />
  <target value="Patient" />
</SearchParameter>