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Physical Therapy

Guide to locating research evidence and tools for Physical Therapy students and faculty.

What is Grey Literature?

Grey literature (GL) is defined as:

  • materials not published commercially or indexed by major databases
  • "Fugitive," "ephemeral," "invisible" literature that may be unpublished, unevaluated, not peer-reviewed
  • "Information produced on all levels of government, academics, business and industry in electronic and print formats not controlled by commercial publishing i.e. where publishing is not the primary activity of the producing body." (Luxembourg, 1997 - Expanded in New York, 2004, http://www.greynet.org/)

Grey Literature may exist in any number of formats:

  • reports
  • preprints
  • conference abstracts and proceedings
  • white papers
  • theses, bibliographies
  • pamphlets
  • official documents
  • newsletters
  • trial registrations
  • patents
  • informal communication (that may include interviews, blog postings, podcasts, personal communication such as email)
  • website information
  • web repositories
  • and more!

 Read more about grey literature:

Sources for Locating Grey Literature:

The following collections of resources offer suggested search engines or databases that can be used to look for different types of grey literature:

Clinical Trial Registries

Research In Progress

Reports, Open Archives & Repositories

Pre-Prints

Meetings & Conference Proceedings

Theses & Dissertations