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Evidence Syntheses & Systematic Reviews: Grey Literature

What is grey literature?

Grey literature includes unpublished studies, unpublished clinical trials, conference proceedings, government and other reports, dissertations/theses and more.

Grey literature is often included in systematic reviews and other types of evidence synthesis to reduce risk of publication bias. 

This 2013 article reports on some of the challenges and benefits of searching out and including grey literature:

Mahood, Q., Van Eerd, D., & Irvin, E. (2014). Searching for grey literature for systematic reviews: Challenges and benefits. Research Synthesis Methods, 5(3), 221–234.

Government and International Databases

Jewell, S. T., Fowler, S., & Foster, M. J. (2017). Identifying the studies (Part 2). In M. Foster & S. Jewell (Eds.).Assesmbling the Pieces of a Systematic Review. Medical Library Assocation Books.

Conference Proceedings & Dissertations

Awarded Grants

PrePrints and Open Archives

Miami University Scholarly Commons

Multidisciplinary Repositories

Medical and Health Sciences Preprints

Note: Also see STEM and Social Sciences Repositories

STEM Repositories

Social Sciences Repositories

Data Repositories

Foreign Preprint Repositories