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12.17.10.1 Operation $apply on ActivityDefinition

Clinical Decision Support Work Group

Maturity Level: 3

Trial Use

Compartments: N/A

The apply operation applies a definition in a specific context.

The official URL for this operation definition is

 http://hl7.org/fhir/OperationDefinition/ActivityDefinition-apply

Formal Definition (as a OperationDefinition).

URL: [base]/ActivityDefinition/$apply

URL: [base]/ActivityDefinition/[id]/$apply

This is an idempotent operation

The result of invoking this operation is a resource of the type specified by the activity definition, with all the definitions resolved as appropriate for the type of resource. Any dynamicValue elements will be evaluated (in the order in which they appear in the resource) and the results applied to the returned resource. If the ActivityDefinition includes library references, those libraries will be available to the evaluated expressions. If those libraries have parameters, those parameters will be bound by name to the parameters given to the operation. In addition, parameters to the $apply operation are available within dynamicValue expressions as context variables, accessible by the name of the parameter, prefixed with a percent (%) symbol. For a more detailed description, refer to the ActivityDefinition resource

12.17.10.1.1 Examples

Request: Apply a citalopram prescription activity definition to a patient

GET [base]/ActivityDefinition/citalopramPrescription/$apply?subject=Patient/124

Response: Returned on successful application

HTTP/1.1 200 OK

<?xml version="1.0" encoding="UTF-8"?>
<MedicationRequest xmlns="http://hl7.org/fhir">
  <!-- This example demonstrates the result of an $apply operation for the citalopramPrescription activity definition. -->
  <id value="apply-operation-response"/>
  <text>
	<status value="generated"/>
    <div xmlns="http://www.w3.org/1999/xhtml">
    Generated...
    </div>
  </text>
  <contained>
    <Medication>
      <id value="citalopramMedication"/>
      <code>
        <coding>
          <system value="http://www.nlm.nih.gov/research/umls/rxnorm"/>
          <code value="200371"/>
        </coding>
        <text value="citalopram"/>
      </code>
        <form>
          <coding>
            <system value="http://snomed.info/sct"/>
            <code value="385055001"/>
            <display value="Tablet dose form"/>
          </coding>
          <text value="Tablet dose form"/>
        </form>
        <ingredient>
          <itemReference>
            <reference value="#citalopramSubstance"/>
          </itemReference>
          <amount>
            <numerator>
              <value value="20"/>
              <unit value="mg"/>
            </numerator>
            <denominator>
              <value value="1"/>
              <unit value="{tbl}"/>
            </denominator>
          </amount>
        </ingredient>
    </Medication>
  </contained>
  <contained>
    <Substance>
      <id value="citalopramSubstance"/>
      <code>
            <system value="http://www.nlm.nih.gov/research/umls/rxnorm"/>
            <code value="2556"/>
        <text value="citalopram"/>
      </code>
    </Substance>
  </contained>
  <status value="draft"/>
  <intent value="proposal"/>
  <medicationReference>
	  <reference value="#citalopramMedication"/>
  </medicationReference>
  <subject>
	  <reference value="Patient/124"/>
  </subject>
  <!--definition>
    <reference value="http://example.org/fhir/ActivityDefinition/citalopramPrescription"/>
  </definition-->
  <instantiates value="http://example.org/fhir/ActivityDefinition/citalopramPrescription"/>
  <dosageInstruction>
	<text value="1 tablet oral 1 time daily"/>
	<timing>
		<repeat>
			<frequency value="1"/>
			<period value="1"/>
			<periodUnit value="d"/>
		</repeat>
	</timing>
	<route>
		<coding>
			<code value="26643006"/>
			<display value="Oral route (qualifier value)"/>
		</coding>
		<text value="Oral route (qualifier value)"/>
	</route>
	<doseAndRate>
	    <type>
	      <text value="ordered"/>
	    </type>
	    <doseQuantity>
			<value value="1"/>
			<unit value="{tbl}"/>
	    </doseQuantity>
	</doseAndRate>
  </dosageInstruction>
  <dispenseRequest>
	  <numberOfRepeatsAllowed value="3"/>
	  <quantity>
		  <value value="30"/>
		  <unit value="{tbl}"/>
	  </quantity>
  </dispenseRequest>
</MedicationRequest>

For more information about operations, including how they are invoked, see Operations.