United States National Library of Medicine National Institutes of Health

Leasing Unified Medical Language System (UMLS) Data

Content
The purpose of the UMLS is to aid the development of systems that help health professionals and researchers retrieve and integrate electronic biomedical information from a variety of sources and to make it easy for users to link disparate information systems, including computer-based patient records, bibliographic databases, factual databases, and expert systems. The UMLS project develops "Knowledge Sources" that can be used by a wide variety of applications programs to overcome retrieval problems caused by differences in terminology and the scattering of relevant information across many databases.

There are three UMLS Knowledge Sources:

The Metathesaurus provides a uniform, integrated distribution format from over 100 biomedical vocabularies and classifications, and links many different names for the same concepts. The Lexicon contains syntactic information for many terms, component words, and English words, including verbs, including some that do not appear in the Metathesaurus. The Semantic Network contains information about the types or categories (e.g., "Disease or Syndrome," "Virus") to which all Metathesaurus concepts have been assigned and the permissible relationships among these types (e.g., "Virus" causes "Disease or Syndrome"). NLM also distributes associated lexical programs and software (MetamorphoSys) helpful in producing customized versions of the UMLS Metathesaurus.

Specifications
All the Knowledge Sources are available to licensed users via the Internet from the UMLS Knowledge Source Server which has a Web interface and an applications program interface (API). Relational files downloadable from the Server are available and may also be requested on DVD.

How to Lease
There is no charge for licensing any part of the UMLS from NLM.

UMLS Metathesaurus
Accept the Web-based UMLS Metathesaurus license agreement and its appendices, and type in name and address information.

Licensees may have to establish separate license agreements with the producers of some specific vocabularies included in the Metathesaurus. Some of the material in the UMLS Metathesaurus is from copyrighted sources. For more information on use and restrictions, see http://wwwcf.nlm.nih.gov/umlslicense/snomed/license.cfm

Licensees are prohibited from distributing the UMLS products or subsets of these products, including individual vocabulary sources within the Metathesaurus, except as an integral part of computer applications developed by the licensee for a purpose other than redistribution of data contained in the UMLS products. Licensees agree to inform NLM prior to distributing any application(s) that use the UMLS products.

Within 30 days of the end of any calendar year in which the licensee makes use of the UMLS Metathesaurus, the licensee agrees to provide NLM with a brief report on the usefulness of the UMLS Metathesaurus in general and, if applicable, on the usefulness of the American Medical Association's CPT-Current Procedural Terminology® in the UMLS format in particular. Licensees will be notified each year with the Web URL location for the UMLS Annual Report template.

SPECIALIST Lexicon
After reading and accepting the the terms and conditions (http://lexsrv3.nlm.nih.gov/SPECIALIST/docs/TermsAndConditions.html) users may download these files from the SPECIALIST Lexicon website (http://SPECIALIST.nlm.nih.gov). There are no other license requirments.

The SPECIALIST Lexicon is also available through the UMLS Knowledge Source Server (http://umlsks.nlm.nih.gov/). A Metathesaurus license number is required to access the UMLS Knowledge Source Server.

UMLS Semantic Network
After reading and accepting the the terms and conditions (http://semanticnetwork.nlm.nih.gov/TermsAndConditions/) users may download these files from the UMLS Semantic Network website (http://semanticnetwork.nlm.nih.gov/). There are no other license requirments.

The UMLS Semantic Network is also available through the UMLS Knowledge Source Server (http://umlsks.nlm.nih.gov/). A Metathesaurus license number is required to access the UMLS Knowledge Source Server.

Alternative to Licensing
None.

Additional Information
A complete description of the Knowledge Sources and their distribution formats can be found in the UMLS Documentation.

For more information about leasing the UMLS Metathesaurus, e-mail custserv@nlm.nih.gov.

Last reviewed: 01 March 2007
Last updated: 22 August 2007
First published: 29 November 2005
Metadata| Permanence level: Permanence Not Guaranteed