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MEDLINE Indexing Online Training Course

Category H - Natural Science Disciplines and Health Occupations

Indexing Principles

Category H1 contains the MeSH headings for the natural science disciplines such as:


Category H2 contains the MeSH headings for the various health occupations such as:


Several of the MeSH headings in these categories exist also as subheadings. The MeSH headings are used for general aspects of the field while the subheadings are used with specific anatomical terms, diseases, organisms, biological processes, and drugs. The indexer will use the subheadings much more frequently than the "duplicate" MeSH heading.

Category H MeSH Heading Subheading
ANATOMY /anatomy and histology
PHYSIOLOGY /physiology
PHARMACOLOGY /pharmacology


Many of the terms in this category are also located in other categories as well, such as Category E -Techniques and Category N6 -Environment and Public Health.

Last Reviewed: March 10, 2015