Operation-valueset-expand.xml

Operation Definition

<OperationDefinition xmlns="http://hl7.org/fhir">
  <id value="ValueSet-expand"/> 
  <text> 
    <status value="generated"/> 
    <div xmlns="http://www.w3.org/1999/xhtml">
      <h2> Value Set Expansion</h2> 
      <p> OPERATION: Value Set Expansion</p> 
      <p> The official URL for this operation definition is: </p> 
      <pre> http://hl7.org/fhir/OperationDefinition/ValueSet-expand</pre> 
      <div> 
        <p> The definition of a value set is used to create a simple collection of codes suitable
           for use for data entry or validation.   If the operation is not called at the instance
           level, one of the in parameters identifier, context or valueset must be provided.  An
           expanded value set will be returned, or an OperationOutcome with an error message.</p> 

      </div> 
      <p> URL: [base]/ValueSet/$expand</p> 
      <p> URL: [base]/ValueSet/[id]/$expand</p> 
      <p> Parameters</p> 
      <table class="grid">
        <tr> 
          <td> 
            <b> Use</b> 
          </td> 
          <td> 
            <b> Name</b> 
          </td> 
          <td> 
            <b> Cardinality</b> 
          </td> 
          <td> 
            <b> Type</b> 
          </td> 
          <td> 
            <b> Binding</b> 
          </td> 
          <td> 
            <b> Documentation</b> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> url</td> 
          <td> 0..1</td> 
          <td> uri</td> 
          <td/>  
          <td> 
            <div> 
              <p> A canonical url for a value set. The server must know the value set (e.g. it is defined
                 explicitly in the server's value sets, or it is defined implicitly by some code system
                 known to the server</p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> valueSet</td> 
          <td> 0..1</td> 
          <td> ValueSet</td> 
          <td/>  
          <td> 
            <div> 
              <p> The value set is provided directly as part of the request. Servers may choose not to accept
                 value sets in this fashion</p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> context</td> 
          <td> 0..1</td> 
          <td> uri</td> 
          <td/>  
          <td> 
            <div> 
              <p> The context of the value set, so that the server can resolve this to a value set to expand.
                 The recommended format for this URI is [Structure Definition URL]#[name or path into structure
                 definition] e.g. http://hl7.org/fhir/StructureDefinition/observation-hspc-height-hspcheight#Observat
                ion.interpretation. Other forms may be used but are not defined. This form is only usable
                 if the terminology server also has access to the profile registry that the server is using,
                 but can be used to delegate the mapping from an application context to a binding at run-time</p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> filter</td> 
          <td> 0..1</td> 
          <td> string</td> 
          <td/>  
          <td> 
            <div> 
              <p> A text filter that is applied to restrict the codes that are returned (this is useful
                 in a UI context). The interpretation of this is delegated to the server in order to allow
                 to determine the most optimal search approach for the context</p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> profile</td> 
          <td> 0..1</td> 
          <td> uri</td> 
          <td/>  
          <td> 
            <div> 
              <p> A reference to an external definition that provides additional control information about
                 how the expansion is performed.  At this time, there is no agreed format or functionality
                 for the target of this URI. The 
                <a href="http://www.nlm.nih.gov/vsac/support/authorguidelines/updatingvaluesets.html">VSAC Documentation</a>  provides one example of the use of this parameter.  Implementers using this element will
                 need to agree on an appropriate mechanism for use within their interoperability community.
                  Known uses for profile include: * whether to return the value set content logical definition
                 with the expansion * whether to include inactive concepts
              </p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> date</td> 
          <td> 0..1</td> 
          <td> dateTime</td> 
          <td/>  
          <td> 
            <div> 
              <p> The date for which the expansion should be generated.  if a date is provided, it means
                 that the server should use the value set / code system definitions as they were on the
                 given date, or return an error if this is not possible.  Normally, the date is the current
                 conditions (which is the default value) but under some circumstances, systems need to
                 generate an expansion as it would have been in the past. A typical example of this would
                 be where code selection is constrained to the set of codes that were available when the
                 patient was treated, not when the record is being edited. Note that which date is appropriate
                 is a matter for implementation policy.</p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> offset</td> 
          <td> 0..1</td> 
          <td> integer</td> 
          <td/>  
          <td> 
            <div> 
              <p> Paging support - where to start if a subset is desired (default = 0). Offset is number
                 of records (not number of pages)</p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> count</td> 
          <td> 0..1</td> 
          <td> integer</td> 
          <td/>  
          <td> 
            <div> 
              <p> Paging support - how many codes should be provided in a partial page view. Paging only
                 applies to flat expansions - servers ignore paging if the expansion is not flat.  If count
                 = 0, the client is asking how large the expansion is. Servers SHOULD honor this request
                 for hierarchical expansions as well, and simply return the overall count</p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> includeDesignations</td> 
          <td> 0..1</td> 
          <td> boolean</td> 
          <td/>  
          <td> 
            <div> 
              <p> Controls whether concept designations are to be included or excluded in value set expansions.
                 Overrides the value in the expansion profile if there is one</p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> includeDefinition</td> 
          <td> 0..1</td> 
          <td> boolean</td> 
          <td/>  
          <td> 
            <div> 
              <p> Controls whether the value set definition is included or excluded in value set expansions.
                 Overrides the value in the expansion profile if there is one</p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> activeOnly</td> 
          <td> 0..1</td> 
          <td> boolean</td> 
          <td/>  
          <td> 
            <div> 
              <p> Controls whether inactive concepts are included or excluded in value set expansions. Overrides
                 the value in the expansion profile if there is one. Note that if the value set explicitly
                 specifies that inactive codes are included, this parameter can still remove them from
                 a specific expansion, but this parameter cannot include them if the value set excludes
                 them</p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> excludeNested</td> 
          <td> 0..1</td> 
          <td> boolean</td> 
          <td/>  
          <td> 
            <div> 
              <p> Controls whether or not the value set expansion nests codes or not (i.e. ValueSet.expansion.contains
                .contains). Overrides the value in the expansion profile if there is one</p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> excludeNotForUI</td> 
          <td> 0..1</td> 
          <td> boolean</td> 
          <td/>  
          <td> 
            <div> 
              <p> Controls whether or not the value set expansion includes codes which cannot be displayed
                 in user interfaces. Overrides the value in the expansion profile if there is one</p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> excludePostCoordinated</td> 
          <td> 0..1</td> 
          <td> boolean</td> 
          <td/>  
          <td> 
            <div> 
              <p> Controls whether or not the value set expansion includes post coordinated codes. Overrides
                 the value in the expansion profile if there is one</p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> displayLanguage</td> 
          <td> 0..1</td> 
          <td> code</td> 
          <td/>  
          <td> 
            <div> 
              <p> Specifies the language to be used for description in the expansions i.e. the language
                 to be used for ValueSet.expansion.contains.display. Overrides the value in the expansion
                 profile if there is one</p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> IN</td> 
          <td> limitedExpansion</td> 
          <td> 0..1</td> 
          <td> boolean</td> 
          <td/>  
          <td> 
            <div> 
              <p> If the value set being expanded is incomplete (because it is too big to expand), return
                 a limited expansion (a subset) with an indicator that expansion is incomplete. Overrides
                 the value in the expansion profile if there is one</p> 

            </div> 
          </td> 
        </tr> 
        <tr> 
          <td> OUT</td> 
          <td> return</td> 
          <td> 1..1</td> 
          <td> ValueSet</td> 
          <td/>  
          <td> 
            <div> 
              <p> The result of the expansion</p> 

            </div> 
          </td> 
        </tr> 
      </table> 
      <div> 
        <p> The value set expansion returned by this query should be treated as a transient result
           that will change over time (whether it does or not depends on how the value set is specified),
           so applications should repeat the operation each time the value set is used.
          <br/>  
        </p> 

        <p> If the expansion is too large (at the discretion of the server), the server will return
           an error (OperationOutcome with code too-costly). Clients can work through large flat
           expansions in a set of pages (partial views of the full expansion) instead of just getting
           the full expansion in a single exchange by using offset and count parameters. Servers
           are not obliged to support paging, but if they do, SHALL support both the offset and count
           parameters. Hierarchical expansions are not subject to paging and servers simply return
           the entire expansion.
          <br/>  
        </p> 

        <p> Different servers may return different results from expanding a value set for the following
           reasons:
          <br/>  
        </p> 

        <ul> 

          <li> The underlying code systems are different (e.g. different versions, possibly with different
             defined behavior)</li> 

          <li> The server optimizes filter includes differently, such as sorting by code frequency</li> 

          <li> Servers introduce arbitrary groups to assist a user to navigate the lists based either
             on extensions in the definition, or additional knowledge available to the server</li> 

        </ul> 

        <p> When a server cannot correctly expand a value set because it does not fully understand
           the code systems (e.g. it has the wrong version, or incomplete definitions) then it SHALL
           return an error. If the value set itself is unbounded due to the inclusion of post-coordinated
           value sets (e.g. SNOMED CT, UCUM), then the extension 
          <a href="extension-valueset-unclosed.html">http://hl7.org/fhir/StructureDefinition/valueset-unclosed</a>  can be used to indicate that the expansion is incomplete
        </p> 

      </div> 
    </div> 
  </text> 
  <url value="http://hl7.org/fhir/OperationDefinition/ValueSet-expand"/> 
  <name value="Value Set Expansion"/> 
  <status value="draft"/> 
  <kind value="operation"/> 
  <date value="2019-10-24T11:53:00+11:00"/> 
  <publisher value="HL7 (FHIR Project)"/> 
  <contact> 
    <telecom> 
      <system value="url"/> 
      <value value="http://hl7.org/fhir"/> 
    </telecom> 
    <telecom> 
      <system value="email"/> 
      <value value="fhir@lists.hl7.org"/> 
    </telecom> 
  </contact> 
  <description value="The definition of a value set is used to create a simple collection of codes suitable
   for use for data entry or validation.   If the operation is not called at the instance
   level, one of the in parameters identifier, context or valueset must be provided.  An
   expanded value set will be returned, or an OperationOutcome with an error message."/> 
  <code value="expand"/> 
  <comment value="The value set expansion returned by this query should be treated as a transient result
   that will change over time (whether it does or not depends on how the value set is specified),
   so applications should repeat the operation each time the value set is used.  

If the expansion is too large (at the discretion of the server), the server will return
   an error (OperationOutcome with code too-costly). Clients can work through large flat
   expansions in a set of pages (partial views of the full expansion) instead of just getting
   the full expansion in a single exchange by using offset and count parameters. Servers
   are not obliged to support paging, but if they do, SHALL support both the offset and count
   parameters. Hierarchical expansions are not subject to paging and servers simply return
   the entire expansion.  

Different servers may return different results from expanding a value set for the following
   reasons:  

* The underlying code systems are different (e.g. different versions, possibly with different
   defined behavior) 
* The server optimizes filter includes differently, such as sorting by code frequency
   
* Servers introduce arbitrary groups to assist a user to navigate the lists based either
   on extensions in the definition, or additional knowledge available to the server

When a server cannot correctly expand a value set because it does not fully understand
   the code systems (e.g. it has the wrong version, or incomplete definitions) then it SHALL
   return an error. If the value set itself is unbounded due to the inclusion of post-coordinated
   value sets (e.g. SNOMED CT, UCUM), then the extension [http://hl7.org/fhir/StructureDefinition/value
  set-unclosed](extension-valueset-unclosed.html) can be used to indicate that the expansion
   is incomplete"/> 
  <resource value="ValueSet"/> 
  <system value="false"/> 
  <type value="true"/> 
  <instance value="true"/> 
  <parameter> 
    <name value="url"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="A canonical url for a value set. The server must know the value set (e.g. it is defined
     explicitly in the server's value sets, or it is defined implicitly by some code system
     known to the server"/> 
    <type value="uri"/> 
  </parameter> 
  <parameter> 
    <name value="valueSet"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="The value set is provided directly as part of the request. Servers may choose not to accept
     value sets in this fashion"/> 
    <type value="ValueSet"/> 
  </parameter> 
  <parameter> 
    <name value="context"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="The context of the value set, so that the server can resolve this to a value set to expand.
     The recommended format for this URI is [Structure Definition URL]#[name or path into structure
     definition] e.g. http://hl7.org/fhir/StructureDefinition/observation-hspc-height-hspcheight#Observat
    ion.interpretation. Other forms may be used but are not defined. This form is only usable
     if the terminology server also has access to the profile registry that the server is using,
     but can be used to delegate the mapping from an application context to a binding at run-time"/> 
    <type value="uri"/> 
  </parameter> 
  <parameter> 
    <name value="filter"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="A text filter that is applied to restrict the codes that are returned (this is useful
     in a UI context). The interpretation of this is delegated to the server in order to allow
     to determine the most optimal search approach for the context"/> 
    <type value="string"/> 
  </parameter> 
  <parameter> 
    <name value="profile"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="A reference to an external definition that provides additional control information about
     how the expansion is performed.  At this time, there is no agreed format or functionality
     for the target of this URI. The [VSAC Documentation](http://www.nlm.nih.gov/vsac/support/authorguide
    lines/updatingvaluesets.html) provides one example of the use of this parameter.  Implementers
     using this element will need to agree on an appropriate mechanism for use within their
     interoperability community.  Known uses for profile include: * whether to return the value
     set content logical definition with the expansion * whether to include inactive concepts"/> 
    <type value="uri"/> 
  </parameter> 
  <parameter> 
    <name value="date"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="The date for which the expansion should be generated.  if a date is provided, it means
     that the server should use the value set / code system definitions as they were on the
     given date, or return an error if this is not possible.  Normally, the date is the current
     conditions (which is the default value) but under some circumstances, systems need to
     generate an expansion as it would have been in the past. A typical example of this would
     be where code selection is constrained to the set of codes that were available when the
     patient was treated, not when the record is being edited. Note that which date is appropriate
     is a matter for implementation policy."/> 
    <type value="dateTime"/> 
  </parameter> 
  <parameter> 
    <name value="offset"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="Paging support - where to start if a subset is desired (default = 0). Offset is number
     of records (not number of pages)"/> 
    <type value="integer"/> 
  </parameter> 
  <parameter> 
    <name value="count"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="Paging support - how many codes should be provided in a partial page view. Paging only
     applies to flat expansions - servers ignore paging if the expansion is not flat.  If count
     = 0, the client is asking how large the expansion is. Servers SHOULD honor this request
     for hierarchical expansions as well, and simply return the overall count"/> 
    <type value="integer"/> 
  </parameter> 
  <parameter> 
    <name value="includeDesignations"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="Controls whether concept designations are to be included or excluded in value set expansions.
     Overrides the value in the expansion profile if there is one"/> 
    <type value="boolean"/> 
  </parameter> 
  <parameter> 
    <name value="includeDefinition"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="Controls whether the value set definition is included or excluded in value set expansions.
     Overrides the value in the expansion profile if there is one"/> 
    <type value="boolean"/> 
  </parameter> 
  <parameter> 
    <name value="activeOnly"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="Controls whether inactive concepts are included or excluded in value set expansions. Overrides
     the value in the expansion profile if there is one. Note that if the value set explicitly
     specifies that inactive codes are included, this parameter can still remove them from
     a specific expansion, but this parameter cannot include them if the value set excludes
     them"/> 
    <type value="boolean"/> 
  </parameter> 
  <parameter> 
    <name value="excludeNested"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="Controls whether or not the value set expansion nests codes or not (i.e. ValueSet.expansion.contains
    .contains). Overrides the value in the expansion profile if there is one"/> 
    <type value="boolean"/> 
  </parameter> 
  <parameter> 
    <name value="excludeNotForUI"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="Controls whether or not the value set expansion includes codes which cannot be displayed
     in user interfaces. Overrides the value in the expansion profile if there is one"/> 
    <type value="boolean"/> 
  </parameter> 
  <parameter> 
    <name value="excludePostCoordinated"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="Controls whether or not the value set expansion includes post coordinated codes. Overrides
     the value in the expansion profile if there is one"/> 
    <type value="boolean"/> 
  </parameter> 
  <parameter> 
    <name value="displayLanguage"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="Specifies the language to be used for description in the expansions i.e. the language
     to be used for ValueSet.expansion.contains.display. Overrides the value in the expansion
     profile if there is one"/> 
    <type value="code"/> 
  </parameter> 
  <parameter> 
    <name value="limitedExpansion"/> 
    <use value="in"/> 
    <min value="0"/> 
    <max value="1"/> 
    <documentation value="If the value set being expanded is incomplete (because it is too big to expand), return
     a limited expansion (a subset) with an indicator that expansion is incomplete. Overrides
     the value in the expansion profile if there is one"/> 
    <type value="boolean"/> 
  </parameter> 
  <parameter> 
    <name value="return"/> 
    <use value="out"/> 
    <min value="1"/> 
    <max value="1"/> 
    <documentation value="The result of the expansion"/> 
    <type value="ValueSet"/> 
  </parameter> 
</OperationDefinition>