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Unified Medical Language System® (UMLS®)

Accessing MetamorphoSys

The procedure to access MetamorphoSys and the UMLS is: by downloading all of the release files from the UMLS Terminology Services (UTS). The release files are quite large; downloading is only recommended with a high speed Internet connection.

To download the files from the UTS:

  1. Login to the UTS
  2. Select the "Downloads" link in the File Menu
  3. Click on the name of the desired release
  4. Click on a file name
  5. Select 'Save file'
  6. Repeat steps 4 & 5 for each file in the release

UMLS files are named with the year of the release and a letter code that indicates their position in the order of releases for that year. Filenames change to reflect the release year and version. For example, the first release of the year is always labeled 'AA', such as 2008AA. The second release of the year 2008 would be 2008AB, the third 2008AC. There are typically two releases a year, one in the Spring and one in the Fall. Additional releases are developed based on NLM resources and user needs.

Below are the eight release files included in the 2010AA Release.



Last Reviewed: March 6, 2017