ConceptMap Translate

Medplum implements the ConceptMap/$translate operation, which allows mapping a coded value between code systems.

Invoke the $translate operation

[base]/ConceptMap/$translate
[base]/ConceptMap/[id]/$translate

Parameters

Name	Type	Description	Required
url	uri	Canonical URL of the ConceptMap, if not specified by ID	No
source	uri	Canonical URL of source ValueSet, used to look up ConceptMap	No
code	code	Code to translate using the ConceptMap	No
system	uri	System the code (above) is drawn from	No
coding	Coding	Full coding to translate using the ConceptMap	No
codeableConcept	CodeableConcept	Concept with one or more codes to translate using the ConceptMap	No
targetsystem	uri	Target code system, used to filter results	No

Required Parameters

Although no individual parameter for the operation is required, both of the following must be satisfied for the operation to proceed:

• Either the ConceptMap ID must be present in the request path (e.g. by calling ConceptMap/[id]/$translate), or one of url or source must be populated to look up the ConceptMap
• Exactly one of the following must be set to specify the source code(s) to translate:
  • Both code and system
  • coding
  • codeableConcept

Example

As an example, assume the following ConceptMap resource exists in the system:

{
  "resourceType": "ConceptMap",
  "url": "http://example.com/concept-map",
  "status": "active",
  "sourceCanonical": "http://example.com/labs",
  "group": [
    {
      "source": "http://snomed.info/sct",
      "target": "http://loinc.org",
      "element": [
        {
          "code": "313444004",
          "target": [
            {
              "code": "15067-2",
              "display": "Follitropin Qn",
              "equivalence": "equivalent"
            }
          ]
        }
      ]
    },
    {
      "source": "http://snomed.info/sct",
      "target": "http://www.ama-assn.org/go/cpt",
      "element": [
        {
          "code": "313444004",
          "target": [{ "code": "83001", "equivalence": "equivalent" }]
        }
      ]
    }
  ]
}

To translate a code using this ConceptMap, one would make an API request like the following:

curl 'https://api.medplum.com/fhir/R4/ConceptMap/[id]/$translate' \
  -X POST \
  -H "Content-Type: application/fhir+json" \
  -H "Authorization: Bearer $ACCESS_TOKEN" \
  -d '{"resourceType":"Parameters","parameter":[ {"name":"code","valueCode":"313444004"}, {"name":"system","valueUri":"http://snomed.info/sct"} ]}'

Success Response

Example outcome:

{
  "resourceType": "Parameters",
  "parameter": [
    { "name": "result", "valueBoolean": true },
    {
      "name": "match",
      "part": [
        { "name": "equivalence", "valueCode": "equivalent" },
        { "name": "concept", "valueCoding": {
          "system": "http://loinc.org",
          "code": "15067-2",
          "display": "Follitropin Qn"
        }}
      ]
    }
    {
      "name": "match",
      "part": [
        { "name": "equivalence", "valueCode": "equivalent" },
        { "name": "concept", "valueCoding": {
          "system": "http://www.ama-assn.org/go/cpt",
          "code": "83001"
        }}
      ]
    }
  ]
}

Error Response

Example outcome when ambiguous input parameters are provided, e.g.:

Request:

POST /fhir/R4/ConceptMap/$translate

{
  "resourceType": "Parameters",
  "parameter": [
    { "name": "url", "valueCode": "http://example.com/concept-map" },
    { "name": "code", "valueCode": "foo" },
    { "name": "system", "valueUri": "http://example.com/code-system" },
    { "name": "coding", "valueCoding": { "code": "bar", "system": "http://example.com/code-system" } }
  ]
}

Response:

400 Bad Request

{
  "resourceType": "OperationOutcome",
  "issue": [
    {
      "severity": "error",
      "code": "invalid",
      "details": { "text": "Ambiguous input: multiple source codings provided" }
    }
  ]
}