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UMLS API Technical Documentation

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Check out the Postman sample collection to help you get started using the UMLS REST API.

API Terms of Service

Retrieving Source-Asserted Parents and Children

URIs | Query Parameters | Sample Output

URIs with /parents or /children 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/SNOMEDCT_US/9468002/parents Retrieves parents a source-asserted identifier SourceAtomCluster*
/content/current/source/SNOMEDCT_US/9468002/children Retrieves children of a source-asserted identifier SourceAtomCluster*

Python example - Retrieve ancestors, descendants, parents, or children

*Calls using codes from HL7V2.5 and HL7V3.0 return output with an “Atom” JSON Object classType.

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
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/current/source/SNOMEDCT_US/9468002/parents?apiKey=YOUR_APIKEY…

{
	"pageSize" : 25,
	"pageNumber" : 1,
	"pageCount" : 1,
	"result" : [{
			"classType" : "SourceAtomCluster",
			"ui" : "36991002",
			"suppressible" : false,
			"obsolete" : false,
			"rootSource" : "SNOMEDCT_US",
			"atomCount" : 5,
			"cVMemberCount" : 0,
			"attributes" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/36991002/attributes",
			"atoms" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/36991002/atoms",
			"descendants" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/36991002/descendants",
			"ancestors" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/36991002/ancestors",
			"parents" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/36991002/parents",
			"children" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/36991002/children",
			"relations" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/36991002/relations",
			"definitions" : "NONE",
			"concepts" : "https://uts-ws.nlm.nih.gov/rest/search/2016AA?string=36991002&sabs=SNOMEDCT_US&searchType=exact&inputType=sourceUi",
			"defaultPreferredAtom" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/36991002/atoms/preferred",
			"name" : "Closed fracture of upper limb"
		}, {
			"classType" : "SourceAtomCluster",
			"ui" : "82065001",
			"suppressible" : false,
			"obsolete" : false,
			"rootSource" : "SNOMEDCT_US",
			"atomCount" : 7,
			"cVMemberCount" : 0,
			"attributes" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/82065001/attributes",
			"atoms" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/82065001/atoms",
			"descendants" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/82065001/descendants",
			"ancestors" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/82065001/ancestors",
			"parents" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/82065001/parents",
			"children" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/82065001/children",
			"relations" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/82065001/relations",
			"definitions" : "NONE",
			"concepts" : "https://uts-ws.nlm.nih.gov/rest/search/2016AA?string=82065001&sabs=SNOMEDCT_US&searchType=exact&inputType=sourceUi",
			"defaultPreferredAtom" : "https://uts-ws.nlm.nih.gov/rest/content/2016AA/source/SNOMEDCT_US/82065001/atoms/preferred",
			"name" : "Fracture of carpal bone"
		}
	]
}