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Clinical Study Types - for Librarians

Clinical Study Types - for Librarians

Medical research librarians are asked to find clinical trials (for example, when constructing the search strategy for a systematic review) but often not provided with guidance on how to do so.  This guide will:

  • provide a modifiable PubMed search string to find each specific type of trial * 
  • define each type of clinical trial, including 
    • definitions from several sources
    • easy-to-understand examples
    • examples from the literature
  • provide hints on how to locate them

*While we provide search strings, it is important to point out that these search strings have not been validated.  They are a compilation of appropriate MeSH terms and keywords, as suggested by:

  • hedges (pre-defined search strings) created to locate these studies
  • definitions of the study type


This guide will NOT provide information on:

  • how to conduct a clinical trial
  • how to evaluate trials (ie risk of bias)


Comments? Questions?  We'd love to hear them!  Send your thoughts to my email address:

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