<Observation xmlns="http://hl7.org/fhir">
  <id value="CCO-0125" />
  <status value="final" />
  <category>
    <coding>
      <system value="http://terminology.hl7.org/CodeSystem/observation-category" />
      <code value="clinical" />
      <display value="Clinical" />
    </coding>
  </category>
  <code>
    <coding>
      <system value="http://loinc.org" />
      <code value="75505-8" />
      <display value="Chief complaint" />
    </coding>
    <text value="Chief complaint" />
  </code>
  <subject>
    <reference value="Patient/PAT-0125" />
  </subject>
  <encounter>
    <reference value="Encounter/ENC-0125" />
  </encounter>
  <valueString value="Multiple Sclerosis" />
</Observation>