Medical Subject Headings (MeSH) Indexing Tips

Medical Subject Headings (MeSH) is a list (thesaurus) of keywords or descriptors that describe articles in Index Medicus and MEDLINE. Indexers scan an entire article and assign up to twenty MeSH terms to each article. Terms are chosen to cover both the central aspects of an article (major headings) and other significant information discussed (minor headings).

By using terms from the MeSH thesaurus, all articles on a given topic can be found regardless of the terminology used by the authors.

Specificity -- Each article is indexed to the most specific MeSH terms available, e.g. an article on acne is indexed under acne, but not under skin diseases.

Near Match -- Articles with no exact match are indexed to the closest related MeSH term, e.g. seminal vesiculitis to seminal vesicles, pseudoappendicitis to appendicitis, nursing caps to clothing.

Two Terms -- The most precise way to cover a topic may be two MeSH terms in combination, e.g. jejunitis to jejunal diseases and enteritis.

Textwords -- It is assumed you will use textwords in some cases to define a subject, e.g. tobacco smoke pollution (MeSH term) and passive (textword) to retrieve passive smoking.

Check Tags -- Large-volume concepts are routinely "checked" for in each article by indexers. Check tags pinpoint specific age groups, males or females, humans or animals, publication types, etc.

Drugs -- Drugs are indexed under the generic name, e.g. valium is indexed to diazepam.

Medical Specialty -- There are separate terms for the medical specialty and the disease or organ, e.g. endocrinology is the specialty versus endocrine diseases or endocrine glands.

Neoplasms -- Neoplasms are indexed to site and histologic type, e.g. adenocarcinoma of the colon is indexed to both colonic neoplasms and adenocarcinoma.

Relational Concepts -- Some relational concepts cannot be indexed precisely, e.g., degrees of quality or quantity, specific time relationships, primary versus secondary except for neoplasms, general body positions. Try or experiment with textwords for these concepts. Even then you may not retrieve the relationship you wish.