Keywords are the unofficial terms that are used to describe a concept. These may be plain language terms or highly specialized jargon. They are different from controlled vocabulary because they are not the words used by the database to organize resources. For instance, PsycINFO uses the Subject Term "Neoplasms," but the literature also uses the keyword "cancer."
Synonyms are words that are interchangeable with one another in describing a concept. For instance, "heart attack" and "myocardial infarction" are used interchangeably within the literature to describe an event when the heart stops beating.
Related terms are words that may not be perfectly interchangeable with others, but they may "play nicely" in the literature. These terms may be similar to the original keywords and may appear in conjunction with the original keywords within the literature. For instance, when searching for "mindfulness," you may also see related terms such as "yoga" and "deep breathing."
Boolean Operators (OR, AND)
Boolean operators are commands to the database, instructing the database how to interpret your combination of search terms.
Use the OR operator to search all synonyms and related terms within a concept group.
Use the AND operator to narrow the search to only the literature that discusses all of your concept groups together.