Subject terms or subject descriptors are controlled vocabulary assigned by indexers to help you find all of the documents about a topic even if the keywords in document titles or abstracts differ. Using subject terms usually improves the relevance of search results.
In the ERIC education database, for example, the subject term "program evaluation" is used. See sample results below where a search for peer-reviewed journal articles about bilingual education AND program evaluation finds over 100 citations compared to only four for bilingual education AND program assessment. You can use controlled terms without specifying they be found in the subject field. Selecting the subject field is optional; doing so yields slightly smaller, more focused results.
Subject terms vary by database. Look for them in relevant records and in lists that often display next to results. Some databases also include a thesaurus or list of subject terms that can be browsed.
