Before starting your database search, think about terms that can be used to describe the key concepts in your research question. Start your search with terms that you think make sense. When you find citations that are highly relevant to your research, take a closer look at those records. Examine those records for two types of terms that you can use in your search: subject headings and keywords.
- Subject Heading: A single, assigned term that stands for a concept. For example, in PubMed, any paper that discusses acetylsalicylic acid would be assigned the Medical Subject Heading (MeSH) term aspirin. A search for the MeSH term Aspirin in PubMed should find papers written about aspirin whether or not the word actually appears in the title or abstract.
- Keyword: Term used for a concept in everyday language. For example, if you need to find articles written about bedpans, the Medical Subject Heading (MeSH) term Toilet Facilities in PubMed may be too broad. Just searching for bedpan OR bedpans by typing this directly into the search box might work better.
Subject headings and keywords have different advantages and disadvantages. Keywords can retrieve new articles that do not yet have subject headings assigned to them. You can also use keywords to capture alternative spellings. Subject headings, however, will help you find highly relevant articles, and may mitigate the need to search for synonyms.
When you conduct your search, consider whether it makes sense to use keywords, subject headings, or both.
See "Documenting Your Search" to learn how to keep track of useful terms.