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Classification 2023 Winter Edition

Worldwide source of medical classification resources

Scope of Revision of the 2023 Winter Edition

The major focus of the 2023 winter edition was the evaluation of the 2023 MeSH (Medical Subject Headings) vocabulary 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 2023 vocabulary in the MeSH Browser. Additional minor updates were made to the Index and Schedules.

Summary Statistics for the 2023 Winter Edition

  • 27 New Class Numbers
  • 15 Modified Class Numbers
  • 1 Canceled Class Number
  • 2 Modified Schedule Headers
  • 47 New Index Headings – (37 from 2023 MeSH)
  • 86 Modified Index Headings
  • 3 Deleted Index Headings

Examples of Additions and Changes Based on MeSH 2023

New 2023 Headings Added to Index by Tree (and related maintenance)

Of the 262 new 2023 MeSH descriptors, only 37 were added to the NLM Classification index.  Below is the list of 2023 index terms added by MeSH tree category in addition to other relevant classification maintenance done:

Organisms [B]

Human Papillomavirus Viruses

Diseases [C]

Post-Acute COVID-19 Syndrome (Post-acute COVID-19 syndrome was added to caption at WC 506.5)

 Analytical, Diagnostic and Therapeutic Techniques, and Equipment [E]

Clinical Relevance

Nerve Conduction Studies (new number created: WL 141.5.N3 Nerve conduction studies)

COVID-19 Drug Treatment

Blood Banking

 Psychiatry and Psychology [F]

Suicide Prevention

Psychological Well-Being (Psychological well-being was added to caption at WM 101)

Family Structure

Family Support

Group Dynamics

Phenomena and Processes [G]

Food, Processed (new number created: WA 708 Processed food)

Disciplines and Occupations [H]


Artificial Life

Evidence Gaps

Paramedicine (Paramedicine was added to caption at WA 290)

 Anthropology, Education, Sociology, and Social Phenomena [I]

Forensic Microbiology

Tobacco Control

Residential Segregation

 Named Groups [M]

Navajo People

Australian Aboriginal and Torres Strait Islander Peoples

Maori People    

Combat Medics




Traditional Medicine Practitioners (WZ 112.5.T7 caption changed from Traditional healers to Traditional medicine practitioners)

African People

European People



Pacific Island People

 Health Care [N]

Working Conditions

Blood Donation

Cost-Effectiveness Analysis

Resource-Limited Settings

Access to Primary Care

Main Index Headings Changes Based on MeSH 2023

Of the 27 MeSH headings that were changed, only 14 affected the NLM Classification

2022 MESH

2023 MESH

African Americans   

Black or African American


Amputation, Surgical

Aneurysm, Dissecting  

Aortic Dissection

American Native Continental Ancestry Group  

American Indian or Alaska Native

Asian Americans  



Asian People


Black People



Homeless Persons  

Ill-Housed Persons



Alaskan Natives  

Alaska Natives

Reconstructive Surgical Procedures 

Plastic Surgery Procedures

Waste Water  



White People

Note: The following 2022 changed MeSH headings were deleted from the index:

  • American Indians or Alaska Natives
  • Cervical Intraepithelial Neoplasia
  • SARS Virus


Table G (Geographic Notation) Addition/Changes

The following geographic notations was added based on the new Z1 MeSH 2023 additions:

JA7-- Asia, Southern 


The following geographic notation was modified based on the Z1 MeSH 2023 change:

JA14-- Far East was changed to Asia, Eastern


2023 Summer Edition

The 2023 summer version will be published at the end of August 2023. It will encompass the systematic review of the WR Dermatology and WW Ophthalmology schedules and other miscellaneous updates.