<OperationOutcome xmlns="http://hl7.org/fhir">
  <id value="operationoutcome-example-error" />
  <meta>
    <profile value="http://ontariohealth.ca/fhir/pcr/StructureDefinition/pcr-operationoutcome-contribution" />
  </meta>
  <issue>
    <severity value="error" />
    <code value="required" />
    <details>
      <text value="Patient family name is required." />
    </details>
    <expression value="Patient.name[0].family" />
  </issue>
</OperationOutcome>