Order of Headings
- Primary subject headings appear first in the record, followed by secondary subjects in order of importance, or in order of their appearance in the item, if importance cannot be determined
- At NLM, in distribution of bibliographic records, or as a result of year end processing, headings may appear in alphabetical order, but the primary subjects will always precede the secondary subjects
Format of MeSH Headings
- Generally, the first letter of all words in a descriptor is upper-cased, with the exception of some species names (follow capitalization shown in MeSH Browser)
- All words in a qualifier are lower-cased
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Last Reviewed: June 16, 2017