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Unified Medical Language System® (UMLS®)

The Rich Release Format (RRF) Subset Browser

The RRF Subset Browser provides users with an easy way to search local subsets, print concept reports, and view raw file information for a specific UMLS concept. The RRF Subset Browser is part of the MetamorphoSys installation and customization tool.

Download MetamorphoSys and the UMLS Knowledge Sources files from the UMLS Terminology Services (UTS) by clicking UMLS Knowledge Sources in the Downloads menu on the UTS home page.

Using the RRF Subset Browser

Search for a UMLS concept by:

  • Concept unique identifier (CUI), for example: C0027051
  • String, for example: heart
  • Code, for example: D003924 (the MeSH code for Diabetes Mellitus, Non-Insulin-Dependent)
  • Tree browser. Navigate the hierarchy of terms for a selected UMLS source vocabulary.

Clicking on an item from the Search Results list will display the concept information. Users can view concept data in the easily printed report view or the raw records view.

Users can filter search results by semantic type, content view flag, or source. Users can also change the display using the 'Restrict Searches and Views' option from the Options drop down menu. Other options include limiting the maximum number of child terms displayed and restricting a search string and the results to a specific language.

The UMLS Quick Tour MetamorphoSys RRF Browser Restrict Searches and Views Option is a narrated guide to the many options available that restrict both searches and views in the RRF Browser.

Last Reviewed: July 29, 2016