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UMLS 2015AA Release Available

Wilder V. UMLS 2015AA Release Available. NLM Tech Bull. 2015 May-Jun;(404):e4.

May 12, 2015 [posted]

The 2015AA release of the Unified Medical Language System (UMLS) Knowledge Sources is available for download as of May 11, 2015.

In the new UMLS Release there are:

  • More than 3.1 million concepts and 12 million unique concept names from over 170 source vocabularies
  • The full Metathesaurus requires 24.1 GB of disk space; the active release requires 23.2 GB of disk space.
  • One new RxNorm subsource
    • Metathesaurus CMS Formulary Reference File (MTHCMSFRF)
  • 32 updated English sources and 19 updated translation sources including MeSH, MedDRA, RxNorm, and SNOMED CT (English and Spanish)
  • SPECIALIST Lexicon and Lexical Tools 2015 Releases

Semantic Types

  • As of 2015AA, six previously deprecated semantic types have been removed.� Any CUIs that were categorized with the deprecated semantic types are re-categorized with the parent of the deprecated semantic type.� The following table lists the semantic types that were removed along with their replacements.

    Deleted Semantic Type Replacement Semantic Type
    Neuroreactive Substance or Biogenic Amine Biologically Active Substance
    Organophosphorus Compound Organic Chemical
    Carbohydrate Organic Chemical
    Lipid Organic Chemical
    Steroid Organic Chemical
    Eicosanoid Organic Chemical

MetamorphoSys
MetamorphoSys now allows an additional connection option, TNS service name, when browsing RRF data in an Oracle database.

Release Information
For more information about the release, see the What's New and Updated Sources sections of the Release Documentation.� Additional release statistics are published on the UMLS Web site.

To access the UMLS Release files, you must have an active UMLS Metathesaurus License and a valid UTS account.� You will be prompted for your UTS username and password when downloading the files.�

Additional information regarding the UMLS is available on the UMLS homepage. New users are encouraged to take the UMLS Basics Tutorial and to explore the new UMLS Quick Start Guide, training materials and other information on the New Users' homepage.

Source Release Documentation
2015AA Source Release Documentation Web pages will be published following the release.