Codesystem-operation-compose

R4 Ballot #1 (Mixed Normative/Trial use)

This page is part of the FHIR Specification (v3.3.0: R4 Ballot 2). The current version which supercedes this version is 5.0.0. For a full list of available versions, see the Directory of published versions

4.7.1.4 Operation $compose on CodeSystem

Vocabulary

Work Group

Maturity Level: 5

Trial Use

Compartments: N/A

Given a set of properties, return one or more possible matching codes

This operation takes a set of properties, and examines the code system looking for codes in the code system that match a set of known properties.

When looking for matches, there are 3 possible types of match:

a complete match - a code that represents all the provided properties correctly
a partial match - a code that represents some of the provided properties correctly, and not others
a possible match - a code that may represent the provided properties closely, but may capture less or more precise informationfor some of the properties

The $compose operation can be called in one of 2 modes:

By a human, looking for the best match for a set of properties. In this mode, the server returns a list of complete, possible or partial matches (possibly with comments), so that the user can choose (or not) the most appropriate code
By a machine (typically in a system interface performing a transformation). In this mode, the server returns only a list of complete and partial matches, but no possible matches. The machine can choose a code from the list (or not) based on what properties are not coded

These modes are differentiated by the 'exact' parameter, so the client can indicate whether it only wants exact matches (including partial matches) or whether potential matches based on text matching are desired

The compose operation is still preliminary. The interface can be expected to change as more experience is gained from implementations.

The official URL for this operation definition is

 http://hl7.org/fhir/OperationDefinition/CodeSystem-compose

Formal Definition (as a OperationDefinition).

URL: [base]/CodeSystem/$compose

URL: [base]/CodeSystem/[id]/$compose

This is an idempotent operation

In Parameters:

Name

Cardinality

Type

Binding

Profile

Documentation

system

0..1

uri

The system in which composition is to be performed. This must be provided unless the operation is invoked on a code system instance

version

0..1

string

The version of the system for the inferencing to be performed

property

0..*

One or more properties that contain information to be composed into the code

property.code

1..1

code

Identifies the property provided

property.value

0..1

The value of the property provided

property.subproperty

0..*

Nested Properties (mainly used for SNOMED CT composition, for relationship Groups)

property.subproperty.code

1..1

code

Identifies the sub-property provided

property.subproperty.value

1..1

The value of the sub-property provided

exact

1..1

boolean

Whether the operation is being used by a human, or a machine. If the operation is being used by a human, the terminology server can return a list of possible matches, with commentary. For a machine, the server returns sure matches, or none at all

compositional

0..1

boolean

Post-coordinated expressions are allowed to be returned in the matching codes (mainly for SNOMED CT). Default = false

Out Parameters:

Name

Cardinality

Type

Binding

Profile

Documentation

match

0..*

Concepts returned by the server as a result of the inferencing operation

match.code

1..1

Coding

A code that matches the properties provided

match.unmatched

0..*

One or more properties that contain properties that could not be matched into the code

match.unmatched.code

1..1

code

Identifies the property provided

match.unmatched.value

1..1

The value of the property provided

match.unmatched.property

0..*

Nested Properties (mainly used for SNOMED CT composition, for relationship Groups)

match.unmatched.property.code

1..1

code

Identifies the sub-property provided

match.unmatched.property.value

1..1

The value of the sub-property provided

match.comment

0..1

string

Information about the quality of the match, if operation is for a human

4.7.1.4.1 Examples

Request:

<Parameters xmlns="http://hl7.org/fhir">
  <parameter>
    <name value="system"/>
    <valueUri value="http://snomed.info/sct"/>
  </parameter>
  <parameter>
    <name value="exact"/>
    <valueBoolean value="true"/>
  </parameter>
  <parameter>
    <name value="property"/>
    <part>
      <name value="code"/>
      <valueCode value="focus"/>
    </part>
    <part>
      <name value="value"/>
      <!-- Measurement finding -->
      <valueCode value="118245000"/>
    </part>
  </parameter>
  <parameter>
    <name value="property"/>
    <part>
      <name value="code"/>
      <!-- Interprets -->
      <valueCode value="363714003"/>
    </part>
    <part>
      <name value="value"/>
      <!-- Bilirubin -->
      <valueCode value="302787001"/>
    </part>
  </parameter>
</Parameters>

SNOMED Composition - provide 2 properties, and ask for a single code for the whole (Response):



HTTP/1.1 200 OK
[other headers]

<Parameters xmlns="http://hl7.org/fhir">
    <parameter>
        <name value="match" />
        <part>
            <name value="code" />
            <valueCoding>
                <system value="http://snomed.info/sct" />
                <code value="365786009" />
                <display value="Bilirubin level - finding" />
            </valueCoding>
        </part>
    </parameter>
</Parameters>

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