What is Grey literature:
“…unpublished research may be considered “grey literature.”… Grey literature is produced at all levels of government, academia, business, and industry in print and electronic formats not controlled by commercial publishers. Grey literature can include government reports, committee reports, academic papers, theses, bibliographies, conference papers and abstracts, discussion papers, newsletters, PowerPoint presentations, conference proceedings, program evaluation reports, standards/best practice documents, technical specifications and standards, and working papers(Alberaniet al. 1990). Because of the nature of grey literature, it is often difficult to access through mainstream databases, such as MEDLINE and CINAHL. The majority of grey literature is not peer-reviewed and has limited referencing of information.”
Benzies, K.M. (2006). State-of-the-evidence-reviews: Advantages and challenges of including grey literature. Worldviews of Evidence Based Nursing, 3(2), 55-61. Retrieved from http://www.nursingsociety.org/Publications/Journals/Pages/worldviews.aspx
For information on Grey Literature:
SuReInfo Grey Literature Chapter
Provides definitions, explanations, and instructions related to searching in grey literature sources. Last updated 15 March, 2023.
Dean Giustini, UBC Biomedical Branch Librarian - March 2010. ’Finding the hard to finds: Searching for the grey literature’
CADTH's Grey Matters resource is a free online tool for finding health-related grey literature that are not published commercially and which may be inaccessible via bibliographic databases.
Tracking tool for many common grey literature sources in health