Skip to Main Content
It looks like you're using Internet Explorer 11 or older. This website works best with modern browsers such as the latest versions of Chrome, Firefox, Safari, and Edge. If you continue with this browser, you may see unexpected results.
Skip to main content

Stage 2: Developing the Search: Search Filters & Hedges

Search Filters and Hedges

Search filters are:

  • Also known as hedges
  • Designed to be highly-sensitive, precise, or a balance of both
  • Tested, transparent ‘canned searches’ that are designed to limit search results

Appropriate and good quality filters will save you time when developing the search strategies for your review.  For more information see:

Commonly used filters limit search results by:

Search filters are evaluated on their performance (e.g., validity, sensitivity, specificity, and precision) and are often (but not always) published after their evaluation.

Example of a search filter for randomized control trials:
(Haynes et all., 2005)
  1. clinical
  2. clinical
  4. tu.xs.
  5. OR/1-4

The search filters you use will be dependent on your academic field and study type. Below are some starting points to guide you in the right direction. Please note these filters may or may not be well validated.

Search Filters in the Health Sciences

Search Filters by Study Design

See what health sciences librarians/information specialists are talking about. PubMed Search Strategies is a blog created to share search strategies -