Glanville 2020

Appraisal of: Glanville, J et al (2020) Whichare the most sensitive search filters to identify randomized controlled trials in MEDLINE? J Med Libr Assoc 108(4): 556-563.


Juliet Brown

Sophie Robinson

Full Reference:

Glanville, J et al (2020) Whichare the most sensitive search filters to identify randomized controlled trials in MEDLINE? J Med Libr Assoc108(4): 556-563.

Short description:

Search filters exist to help with the standardised and consistent retrieval of a pre-specified group of studies from bibliographic databases. The Cochrane RCT search filters are an example of such a tool, these were previously tested and adapted in 2008, and were then checked in this 2020 study for their current performance in retrieving appropriate study records. In 2019, the authors tested current Cochrane RCT search filters alongside 36 other known RCT search filters for sensitivity, specificity, and precision by searching within a gold standard set of RCTs from2016. The gold standard set of RCT abstracts was derived from the Cochrane CENTRAL Cochrane Central Register of Controlled Trials) database which uses Medline as one of its sources, the set was then combined with each individual search filter. The authors found that the current Cochrane RCT search filters performed well against other search filters as it has a relatively high sensitivity and a slightly better precision relative to other search filters. If a RCT filter with a balance of sensitivity and precision is required, the authors suggest using the Nwosu et al. (1998) search filter.

Limitations stated by the author(s):

The authors describe the following limitations of this study:

  • The search was conducted on a set of 2016 records with (the then current) 2019 indexing, so the authors were unable to ascertain how the search filters may have performed under actual 2016 conditions with those indexing terms.

  • Some records in CENTRAL may not be reports of controlled clinical trials due to errors in indexing and/or classification, but the impact of their small number within such a large dataset was felt to be minimal.

  • Relative precision is a pragmatic measure of fitness and the use of CENTRAL as a gold standard is the best approximation of RCTs within Medline. There may be some slight discrepancy in reported sensitivity presented in this paper with when re-run under other circumstances.

Limitations stated by the reviewer(s):

No additional limitations detected by the reviewers.

Study Type:

Single study

Related Chapters:

Clinical Effectiveness


  • Search filters


  • Randomised controlled trials