Get Better Search Results!
When searching in databases, there are many advanced search strategies that can help you narrow or broaden your search results. You may know the basics, like narrowing by publish date or language, but below are further strategies that will help you get the best possible search results.
Boolean Operators
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Advanced Search Strategies
Unlike keywords, Subject Headings are the major content in the article; they're also called "controlled vocabulary." A search on the topic altitude training as a keyword may retrieve some articles with 'altitude,' some with 'training' and some with the phrase 'altitude training.' But if the subject heading is 'altitude training' then the article is focused on that topic. Your search may be much broader retrieving more articles with keywords, but in searching with subject headings, you are likely to get fewer but more precise results. Subject headings are also referred to as 'descriptors' in some databases.
More specifically, PubMed and MEDLINE utilize Medical Subject Headings (MeSH), a controlled vocabulary created by the National Library of Medicine.
Thesaurus
Some databases have a thesaurus - a powerful collection of subject headings or standardized terms created by the indexers. Controlled vocabulary provides more effective searching capability in databases where a thesaurus is available. For example you may think of the word 'substance abuse,' but the database thesaurus indexes it as 'drug abuse.'
Use the thesaurus to find keywords and phrases and apply these search terms in the subject field (SU or DE). The results may be better for searches of thesaurus terms in the subject field than for a simple keyword search of the title or abstract of an article.
Make sure to consult the following thesauri when searching these databases:
MEDLINE- MeSH terms (Medical Subject Heading)
CINAHL - subject headings
PsycINFO - thesaurus from APA