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UMLS API Technical Documentation

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API Terms of Service

Retrieving Source-Asserted Relations

URIs | Query Parameters | Sample Output

URIs with /relations support the following use cases:

Note that ‘current’ in the URI can always be used to search against the latest UMLS publication.
You may use any valid UMLS release back to 2008AA in your URI if you would like to search against a particular version of the UMLS.

URIs

The base URI is https://uts-ws.nlm.nih.gov/rest

Sample URI Description Returned JSON Object classType
/content/current/source/LNC/44255-8/relations Retrieves relationships of LOINC code 44255-8 AtomClusterRelation

Query Parameters

Parameter name Required? Y/N Description Valid Values Default value Usage Note
apiKey Y An API key is required for each call to the API. Visit your UTS profile to obtain your API key. n/a n/a n/a
includeRelationLabels N One or more relation labels Any relation label in the UMLS n/a Use a comma between each relation label to specify more than one.
includeAdditionalRelationLabels N One or more relation attribute Any relation attribute in the UMLS n/a Use a comma between each relation attribute to specify more than one.
includeObsolete N Include content that is obsolete according to the content provider or NLM. true or false false n/a
includeSuppressible N Include content that is suppressible according to NLM Editors. true or false false n/a
pageNumber N Whole number that specifies which page of results to fetch. 1,2,3, etc 1 n/a
pageSize N Whole number that specifies the number of results to include per page. 1,2,3, etc 25 n/a

Sample Output

Sample output for https://uts-ws.nlm.nih.gov/rest/content/2015AA/source/LNC/44255-8/relations?includeAdditionalRelationLabels=has_answer&apiKey=YOUR_APIKEY…


{
  "pageSize": 25,
  "pageNumber": 1,
  "pageCount": 1,
  "result": [
    {
      "ui": "R150349583",
      "suppressible": false,
      "sourceUi": "NONE",
      "obsolete": false,
      "sourceOriginated": false,
      "rootSource": "LNC",
      "groupId": "NONE",
      "attributeCount": 1,
      "classType": "AtomClusterRelation",
      "relatedFromId": "https://uts-ws.nlm.nih.gov/rest/content/2015AA/source/LNC/44255-8",
      "relatedFromIdName": "Feeling down, depressed, or hopeless in last 2W:Find:Pt:^Patient:Ord:Reported.PHQ",
      "relationLabel": "RO",
      "additionalRelationLabel": "has_answer",
      "relatedId": "https://uts-ws.nlm.nih.gov/rest/content/2015AA/source/LNC/LA6570-1",
      "relatedIdName": "More than half the days"
    },
    {
      "ui": "R150379228",
      "suppressible": false,
      "sourceUi": "NONE",
      "obsolete": false,
      "sourceOriginated": false,
      "rootSource": "LNC",
      "groupId": "NONE",
      "attributeCount": 1,
      "classType": "AtomClusterRelation",
      "relatedFromId": "https://uts-ws.nlm.nih.gov/rest/content/2015AA/source/LNC/44255-8",
      "relatedFromIdName": "Feeling down, depressed, or hopeless in last 2W:Find:Pt:^Patient:Ord:Reported.PHQ",
      "relationLabel": "RO",
      "additionalRelationLabel": "has_answer",
      "relatedId": "https://uts-ws.nlm.nih.gov/rest/content/2015AA/source/LNC/LA6571-9",
      "relatedIdName": "Nearly every day"
    },
    {
      "ui": "R150401508",
      "suppressible": false,
      "sourceUi": "NONE",
      "obsolete": false,
      "sourceOriginated": false,
      "rootSource": "LNC",
      "groupId": "NONE",
      "attributeCount": 1,
      "classType": "AtomClusterRelation",
      "relatedFromId": "https://uts-ws.nlm.nih.gov/rest/content/2015AA/source/LNC/44255-8",
      "relatedFromIdName": "Feeling down, depressed, or hopeless in last 2W:Find:Pt:^Patient:Ord:Reported.PHQ",
      "relationLabel": "RO",
      "additionalRelationLabel": "has_answer",
      "relatedId": "https://uts-ws.nlm.nih.gov/rest/content/2015AA/source/LNC/LA6569-3",
      "relatedIdName": "Several days"
    },
    {
      "ui": "R150334726",
      "suppressible": false,
      "sourceUi": "NONE",
      "obsolete": false,
      "sourceOriginated": false,
      "rootSource": "LNC",
      "groupId": "NONE",
      "attributeCount": 1,
      "classType": "AtomClusterRelation",
      "relatedFromId": "https://uts-ws.nlm.nih.gov/rest/content/2015AA/source/LNC/44255-8",
      "relatedFromIdName": "Feeling down, depressed, or hopeless in last 2W:Find:Pt:^Patient:Ord:Reported.PHQ",
      "relationLabel": "RO",
      "additionalRelationLabel": "has_answer",
      "relatedId": "https://uts-ws.nlm.nih.gov/rest/content/2015AA/source/LNC/LA6568-5",
      "relatedIdName": "Not at all"
    }
  ]
}