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: https://library.medicine.yale.edu/tutorials/1053

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 trial.mp
2. clinical trial.pt.
3. random:.mp.
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

• University of Alberta Libraries (Canadian focus; includes MEDLINE and EMBASE)
• McMaster HKR Hedges (includes PsycINFO, MEDLINE, EMBASE)
• SIGN - Search Filters (CINAHL, MEDLINE, EMBASE)
• The Inter-TASC Information Specialist Sub-Group Search Filter Resource

Search Filters by Study Design

• Qualitative Research (from the Inter-TASC Information Specialist Sub-Group Search Filter Resource)
• Critical Appraisal of Search Filters  (from the Inter-TASC Information Specialist Sub-Group Search Filter Resource)
• McMaster Hedges Project

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