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NLM Classification Updated, January 31, 2020

February 4, 2020

The 2020 MeSH (Medical Subject Headings) vocabulary was evaluated for inclusion in the Classification index. Several additions and changes were made to the Index and Schedules based on this review. All main index headings are now linked to the 2020 vocabulary in the MeSH Browser. A mini-systematic review of the W 775-867 Medicolegal Examination section was conducted. Additional minor updates were made to the Index and Schedules.

Summary Statistics for the 2020 Winter Edition

59 index main headings added (49 from 2020 MeSH)

155 index entries modified

5 index headings deleted

11 class numbers added [see Class Numbers Added and Canceled (Current Edition)]

338 class number captions or notes modified

3 schedule range headers modified

2 class numbers canceled

For more information about the scope of the 2020 winter edition, see

The 2020 summer version will be published in mid-to-late August 2020. It will encompass the systematic review of the WD (Disorders of Systemic, Metabolic or Environmental Origin, etc.) and WO (Surgery) schedules and other miscellaneous updates. The PDF version will be published annually in the fall.

Contact NLM for further information, or if you have questions or comments.


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Last Reviewed: February 4, 2020