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Unified Medical Language System® (UMLS®)

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Source Vocabularies

Many different types of biomedical vocabularies are included in the Metathesaurus. There are many different ways to categorize them. Some vocabularies fall into more than one category. Major categories include:

  • Diagnosis
    • Logical Observation Identifier Names and Codes (LOINC)
  • Procedures & Supplies
    • Current Procedural Terminology (CPT)
  • Diseases
    • International Classification of Diseases and Related Health Problems (ICD-10)
  • Comprehensive Vocabularies/Thesauri
    • Systematized Nomenclature of Medicine-Clinical Terms (SNOMED CT)

Other categories are anatomy, drugs, genetics, nursing and miscellaneous.

graphic of vocabularies by type
This graph shows the percentage of different vocabulary categories represented in the Metathesaurus.

Last Reviewed: September 1, 2016