While databases like PubMed, Scopus, and Embase are better tools for searching journal literature, there are other sites which are more suitable for searching grey literature.
The term grey literature refers to research that is either unpublished or has been published in non-commercial form. As the growth of the Web has increased opportunities, grey literature is now freely available on many sites. However it is only selectively indexed by database vendors. Many organizations and individuals also provide access to their works online, and most of this material remains unindexed.
Examples of grey literature include:
For a more extensive listing see GreyNet's Document Types in Grey Literature
Jess Tyndall has produced an interesting paper in which she explores the relevance and advantages of grey literature in the research environment.
How low can you go? Towards a hierarchy of grey literature.
Presented at Dreaming08: Australian Library and Information Association Biennial Conference, 2-5 September 2008, Alice Springs.
The Fourth International Conference on Grey Literature held in Washington, DC, in October 1999 defined grey literature as: "that which is produced on all levels of government, academics, business and industry in print and electronic formats, but which is not controlled by commercial publishers."
The AACODS checklist, developed in 2010 by Jess Tyndall of Flinders University, is designed to enable evaluation and critical appraisal of this literature. It highlights the areas of Authority, Accuracy, Coverage, Objectivity, Date and Significance.
Google can be a useful search tool when looking for grey literature
One of the Google options which can be very helpful is site:
site:health.gov.au - will restrict your search to the Australian Goverment's Department of Health and Ageing web site
You can further focus your search by adding a topic
site:health.gov.au obesity - this will focus on Department of Health and Ageing material on obesity
You can also focus your search to look for specific filetypes
site:health.gov.au obesity filetype:doc - this search will retrieve Department of Health and Ageing .doc files on obesity
site:health.gov.au obesity filetype:pdf - this search will retrieve Department of Health and Ageing .pdf files on obesity
For a list of Google searchable file types see http://support.google.com/webmasters/bin/answer.py?hl=en&answer=35287
Google Advanced Search also allows you to limit your search to a site, or domain, eg. gov.au gov.uk, to a geographical region, to a file type, and to a language. It allows phrase searching in combination with multiple options.
Finding theses - in our collection, and from universities throughout the world. A collection of links to relevant sources.
Australasian Open Access Repositories
Maintained by the Australasian Open Access Strategy Group (AOASG)
The Council of Australian University Librarians (CAUL) maintain a list of repository contacts for repositories in Australian and New Zealand universities.
Grey Matters: a practical search tool for evidence-based medicine.
Produced by CADTH (Canadian Agency for Drugs and Technologies in Health).
GreySource, A Selection of Web-based Resources in Grey Literature
GreySource provides examples of grey literature to the average net-user and in so doing profiles organizations responsible for its production and/or processing. Only web-based resources that explicitly refer to the term grey literature (or its equivalent in any language) are listed. GreySource identifies the hyperlink directly embedded in a resource, thus allowing immediate and virtual exposure to grey literature.
Grey literature in meta-analyses of randomized trials of health care interventions
By S Hopewell, S McDonald, M Clarke, and M Egger. This review shows that published trials tend to be larger and show an overall greater treatment effect than grey trials. This has important implications for reviewers who need to ensure they identify grey trials, in order to minimise the risk of introducing bias into their review.
Cochrane Database of Systematic Reviews. 2007, April 18: (2)
MedNar : Deep Medical Web Search
A useful database for searching grey literature - the Advanced Search allows you to target specific organisations and government departments.
Universities world-wide now create institutional repositories to record the research conducted by academics. These are particularly useful sources of grey literature. OpenDOAR is a directory of open access academic repositories. As well as providing a simple repository list, OpenDOAR lets you search for repositories or search repository contents.
OpenGrey is a multidisciplinary European database, covering science, technology, biomedical science, economics, social science and humanities.
PIE (Prevention Information & Evidence eLibrary)
Designed to help you find the latest information and evidence in public health from news to grey literature.
PsycEXTRA is a database which combines bibliographic records with full-text professional and lay-audience literature such as legal testimony and amicus briefs, reports, conference materials, popular magazines, factsheets, grants, and web materials. It is a source for information, research and practice in the behavioural and social sciences and an archive of grey literature documenting psychology's development.
SUMSearch searches a number of key databases, such as MEDLINE, and the Database of Abstracts of Reviews of Effects (DARE) It also searches the National Guideline Clearinghouse and has been expanded to include reports from the Institute of Medicine, AHRQ Evidence-based Practice Centers, National Institute for Health and Clinical Excellence (UK), as well as the Cochrane, and Clinical Evidence. Please note that it is NOT suitable for use as a substitute for PubMed or Cochrane. Its advantage is its inclusion of some grey literature sources.