Skip Navigation Bar
National Library of Medicine Technical BulletinNational Library of Medicine Technical Bulletin

Table of Contents: 2013 NOVEMBER–DECEMBER No. 395

Previous Next

UMLS 2013AB Release Available

Wilder V. UMLS 2013AB Release Available. NLM Tech Bull. 2013 Nov-Dec;(395):e4.

2013 November 22 [posted]

The 2013AB release of the Unified Medical Language System (UMLS) Knowledge Sources is available for download as of November 21, 2013.

In the new UMLS Release there are:

  • More than 2.9 million concepts and 11.4 million unique concept names from over 160 source vocabularies
  • The full Metathesaurus requires 23 GB of disk space; the active release requires 22 GB of disk space.
  • Four new sources
    • Anatomical Therapeutic Chemical Classification System (ATC)
    • Current Dental Terminology (CDT)
    • US Edition of SNOMED CT (SNOMEDCT_US)
    • Vaccines Administered (CVX)
  • One new mapping
    • SNOMED CT-to-ICD10
  • 37 updated English sources and 20 updated translation sources including MeSH, MedDRA, RxNorm, and SNOMED CT® (English and Spanish)

As of 2013AA, the release is available in two versions: Full and Active.

The Full Release includes all source vocabularies.

The Active Release includes only vocabularies that are actively updated in the Metathesaurus. The Active Release is a smaller download, decreases MetamorphoSyS processing time, and provides easier access to current Metathesaurus content.

Data Changes

  • MRCONSO file change: The maximum length for the CODE, SAUI, SCUI, and SDUI fields is now increased to 100 characters.
  • The co-occurrences files, MRCOC.RRF and MRCOC (ORF format), are not included in the release as of 2013AB. Co-occurrence information is available on the MEDLINE/PubMED Baseline Repository (MBR) Web site.
  • The Metathesaurus no longer includes these vocabulary sources, listed by Source abbreviation (SAB):
    • MTHHL7V25 (HL7 Vocabulary Version 2.5, 7-bit equivalents)
    • MTHICPC2ICD107B (International Classification of Primary Care 2nd Edition, 7-bit Equivalents)
    • SNOMEDCT (International Release of SNOMED CT); content is available in SNOMEDCT_US
    • SNOMEDCT_USX (US Extension of SNOMED CT); content is available in SNOMEDCT_US
  • NLM no longer creates plain ASCII versions of atoms where the original string value included non-ASCII characters. As of this release the Metathesaurus does not include these ASCII terms. Metathesaurus indexes reflect these changes and include modifications to maintain existing search and retrieval capabilities.
    • Use the Unicode Filter in MetamorphoSys to convert to ASCII or remove non-ASCII terms from your subset.

Logical Observation Identifier Names and Codes (LOINC)

  • LNC_AD8 (Eight-item Informant Interview to Differentiate Aging and Dementia) and LNC_MDS30 (Minimum Data Set, 3.0):
    • As of 2013AB, this content is included under SAB=LNC due to processing changes.
  • The representation of LOINC (SAB=LNC) in the Metathesaurus does not include the following content:
    • Blessed Orientation-Memory-Concentration Test
    • Borderline Symptom List – 23 Item
    • Borderline Symptom List – Supplement
    • Edinburgh Postnatal Depression Scale
    • Patient Reported Outcomes Measurement (PROMIS)
    • Test of Infant Motor Performance (TIMP)

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
2013AB Source Release Documentation Web pages will be published following the release.

By Victoria Wilder
MEDLARS Management Section

NLM Technical Bulletin National Library of Medicine National Institutes of Health