# GREY literature (UK/AU spelling) | GRAY literature (US spelling)
The term grey literature "is usually understood to mean literature that is not formally published in sources such as books or journal articles" (Lefebvre, Manheimer, & Glanville, 2008). Grey literature may include multiple types of document produced on all levels of government and by academics, businesses and organisations in electronic and print formats where publishing is not the primary activity of the producing body. (Greynet, 2015.) (Murdoch University Library - What is grey literature?)
Examples of grey literature include:
"A wealth of knowledge and information is produced by organisations, governments and industry ... These publications, data and other materials, known as grey literature, are an essential resource in scholarly communication, research and policy making for business, industry, professional practice and civil society. Grey literature is recognised as a key source of evidence, argument, innovation and understanding in many disciplines, including science, engineering, health, social sciences, education, the arts and humanities". (Pisa Declaration, 2014)
Including grey literature can assist to:
Grey literature for systematic and scoping reviews
For systematic and scoping reviews, a grey literature search may be mandatory or strongly recommended. For instance, Cochrane's MECIR standards recommend authors: "Search relevant grey literature sources such as reports, dissertations, theses, databases and databases of conference abstracts. Searches for studies should be as extensive as possible in order to reduce the risk of publication bias and to identify as much relevant evidence as possible." (University of British Columbia Library's - Grey literature for health sciences)
Grey literature to support public policy and practice
Developing a grey literature search strategy > Systematic search frameworks + Documentation strategies > Evaluating grey literature
Searching for grey literature - Tips
Grey literature can form part of a broader search strategy, or be used as a stand-alone search strategy. A clear well-defined question will help to inform your grey literature search and assist with identifying relevant sources and set up clear parameters for your search.
♦Grey literature as part of a research strategy (University of Canberra Library)
♦Finding grey literature - developing a grey literature search plan (James Cook University Library)
♦Searching the grey literature - developing a grey literature search strategy (University of Toronto libraries)
►Identifying Where, What, When and Who(m)
Considerations when developing a grey literature search strategy include:
►Systematic search frameworks | Documentation strategies
♦Grey Matters: A practical tool for searching health-related grey literature [2022 update] (Canadian Drug and Health Technology Agency)
♦How to find and document grey literature (University of Toronto Libraries) - a document template
►Evaluating grey literature
►Finding grey literature > search tips (Jame Cook University Library)
►Finding grey literature > health and medical (Jame Cook University Library)
►Finding the hard to finds: Searching for grey literature – 2012 update (Giustini D, Biomedical Librarian, University of British Columbia, Canada)
►Searching for grey literature. Systematic Review Fact Sheet No. 5 (2020 Nov) (Flinders University Library)
♦Advanced Google operators for grey literature (University of British Columbia Library)
♦Using Google Scholar for grey literature (University of British Columbia Library)
Subjects - Public health; Population health | Epidemiology
Health Disparities Bibliography - key federal reports and historical overviews that define health disparities issues in the United States
♦Advanced Google operators for grey literature (University of British Columbia Library)
♦Using Google Scholar for grey literature (University of British Columbia Library)