Hedges, clinical queries, search filters

If you haven't used hedges, clinical queries or search filters, then you're missing a powerful searchers' tool.

These predefined search strategies are mostly available in databases based on controlled vocabularies but not always. MEDLINE (both PubMed and Ovid), PsycINFO, and to some degree, CINAHL all provide some form of search filters - and of course, each database refers to them by a different name.

Whatever the name (and henceforth my term is 'search filters'), they compensate for indexing inconsistencies, the vagaries of the English language, and different levels of search skill competence.

In MEDLINE, these search filters focus on levels of evidence (RCTs, systematic reviews, etc.), clinical queries (therapy, etiology, diagnosis, prognosis) , or health services research (costs, economics, outcomes assessment). In PsycINFO, filters cover such areas as: achievment measures, attitude measures, neuropsychological assessment, "talking" therapies and more.

How does it work?

• Conduct your topical search.
• Find and run the search filter.
• Using AND, combine the result of your topical search with the final set number of the search filter.

Tune in again for the gory details (PubMed, Ovid, PsycINFO and CINAHL)!