<StructureDefinition xmlns="http://hl7.org/fhir">
  <meta>
    <lastUpdated value="2019-05-07T22:28:14.361-04:00" />
  </meta>
  <text>
    <status value="generated" />
    <div xmlns="http://www.w3.org/1999/xhtml">
      <p>Whether an allergy is Observed (by a clinician during an encounter) or reported by patient or proxy</p>
    </div>
  </text>
  <url value="https://www.VA.gov/FHIR/StructureDefinition/AllergyObservationModeExtension" />
  <name value="AllergyObservationMode" />
  <display value="Observed or Historical" />
  <status value="draft" />
  <date value="2019-02-12T11:11:09.215-05:00" />
  <description value="Whether an allergy is reported as history or a reaction is observed by a clinician" />
  <requirements value="values are 'o' for Observed (by a clinician during an encounter) or 'h' for historical, i.e., reported by patient or proxy" />
  <fhirVersion value="1.0.2" />
  <mapping>
    <identity value="http://www.va.gov/systems/VistAElements/120.8-6" />
    <uri value="http://www.va.gov/systems/VistAElements/120.8-6" />
    <name value="Observed/Historical" />
  </mapping>
  <kind value="datatype" />
  <constrainedType value="Extension" />
  <abstract value="false" />
  <contextType value="resource" />
  <context value="AllergyIntolerance" />
  <base value="http://hl7.org/fhir/StructureDefinition/Extension" />
  <differential>
    <element>
      <path value="Extension" />
      <short value="Observed or Historical" />
      <definition value="Whether an allergy is reported as history or a reaction is observed by a clinician" />
      <comments value="VistA field PATIENT ALLERGIES OBSERVED/HISTORICAL 120.8 - 6&#xD;&#xA;" />
      <max value="1" />
      <mapping>
        <identity value="VistAElements" />
        <map value="120.8-6" />
      </mapping>
    </element>
    <element>
      <path value="Extension.url" />
      <fixedUri value="https://www.VA.gov/FHIR/R2/ExtensionAllergyObservationModeExtension" />
    </element>
    <element>
      <path value="Extension.valueCode" />
      <definition value="Value of extension - binding to value set" />
      <min value="1" />
      <type>
        <code value="code" />
      </type>
      <binding>
        <strength value="required" />
        <valueSetReference>
          <reference value="http://www.va.gov/Terminology/VistADefinedTerms/ValueSet/120.8-6" />
        </valueSetReference>
      </binding>
    </element>
  </differential>
</StructureDefinition>