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Unified Medical Language System® (UMLS®)

Unified Medical Language System (UMLS ) Basics

Welcome to the "Unified Medical Language System (UMLS) Basics," a Web-based learning program that will educate you about the basic principles of the UMLS. By the end of this course students should:

  • Be able to name and describe the three main components of the UMLS
  • Understand that the Metathesaurus contains terminology from a variety of source vocabularies, and be able to explain how it is organized
  • Understand the purpose of the semantic types and relationships in the Semantic Network
  • Be familiar with the MetamorphoSys tool distributed with each UMLS release and required to create a useful Metathesaurus subset
  • Understand how to access the UMLS Terminology Services and how to use the RRF Browser
  • Know where to find additional resources and support

For brief tutorials on specific topics, step-by-step guides, or more advanced documentation see the UMLS Web site.

Using the Tutorial
To complete the tutorial in one session, or move forward in a linear fashion, click Next in the sidebar. For information about a specific topic, click on that topic in the bulleted list on the left hand side of your screen. Each section contains a number of tabs that divide the information into topics. Click Next to continue through the tabs in sequence or click on the tab to access that topic immediately. Note the Glossary available from the left side bar.

NLM welcomes your feedback about this UMLS Basics online course. Please use the Feedback or Contact Us options available from the left side bar using the phrase UMLS Basics in the Subject of my comment/suggestion box.

Last Reviewed: July 29, 2016