Searching grey literature

Grey literature is not controlled by commercial publishing and it is not always peer reviewed. It is generated by diverse sources and come in many formats. It can also be produced by charities and non-profit organisations, societies, special interest groups, professional associations, universities, central government and local authorities, international bodies such as WHO, businesses, market intelligence consultancies, think tanks, political/pressure groups, patient and consumer groups and many more.

Why should I use grey literature?

  • Some material is only available as grey literature e.g. material intended for funding bodies such as the preliminary results of research projects.
  • Excellent source of raw data (e.g. statistics)
  • Rapidly produced and disseminated (only possible without the formal publication process journal articles are subject to) – conference proceedings and results of studies may appear as grey literature over a year before appearing in conventionally published journals.
  • Information can be fuller and more detailed than would be possible in journal articles, as grey literature is not bound by space restrictions.
  • Enables the viewpoints of individuals less likely to publish in journals to be heard – such as patients, victims etc.
  • Published journals may be susceptible to biases against reporting negative or neutral outcomes, a phenomenon known as “positive result bias”. Researching grey literature such as study protocols and clinical trials, can help identify publication biases. See Goldacre, B. (2012) What doctors don’t know about the drugs they prescribe, Available [Accessed 26 January 2024].

Identifying sources, its relevance and credibility are important challenges. Below you will find guides and tutorials on how to find and record your searches of grey literature. In our Grey literature sources and databases page you will find a list of useful websites that can help you with your search. In our Critical Appraisal page you can find tools and strategies to evaluate grey literature.

Guides and tutorials on how to find grey literature

Guides and tutorials on how to find grey literature

Decolonising of Grey Literature: Systematic Review Conversations Series (video with John Barbrook) John Barbrook. Faculty Librarian for Science and Technology, Health and Medicine at Lancaster University talks about early experiences of Decolonising in Systematic Reviews. Provides tips and strategies.
Godin, K., Stapleton, J., Kirkpatrick, S.I. et al. Applying systematic review search methods to the grey literature: a case study examining guidelines for school-based breakfast programs in Canada. Syst Rev 4, 138 (2015). This article demonstrates a feasible and seemingly robust method for applying systematic search strategies to identify web-based resources in the grey literature.
Grey Matters: a practical tool for searching health-related grey literature Discover sources and document your search with this tool from the Canadian Agency for Drugs and Technologies in Health
University of South Australia grey literature guide Techniques for finding grey literature
University of Toronto grey literature guide Steps on finding grey literature. Includes a tutorial and a downloadable template.

Page last reviewed: 27 January, 2024