LibGuides: Information sources: Grey literature

What is grey literature?

Grey literature refers to both published and unpublished research material that is not available commercially. It is often of a scientific or technical nature and is not available through the usual bibliographic sources, such as databases or indexes.

It is produced by government departments, universities, corporations, associations and societies, and professional organisations.

Some examples:

technical reports
standards
conference proceedings
newsletters
government documents
white papers
patents
bulletins

What are the features of grey literature?

Grey literature is often created by practitioners or organisations, so authorship is not always academic. Academics may also be asked to contribute to grey literature, such as authoring research reports, or they may also publish their own in progress research via conference papers, presentations or via other platforms.
It is rapidly produced, so can be very current.
It might be very detailed and geographically specific.
It is often intended for small or specific audiences.
It can be difficult to find.
it is not peer reviewed, so will need to be evaluated carefully for authority, accuracy, objectivity and significance.

Finding grey literature

Grey literature, due to its diverse origins and unpublished nature, can be difficult to find. It is often found by searching for the agency or institution who is most likely to produce the literature. The search may require looking at a large number of sources.

Here are a few places to start looking:

Start your search by choosing from the options listed below.
Search the corporation, institution, or agency that is most likely to produce the type of information you are looking for.
Search online catalogues.
Consult your academic liaison librarian.

Places to search for grey literature

Searching the online catalogue of large libraries for grey literature can be fruitful.

WorldCat
WorldCat holds millions of holdings from numerous libraries world-wide.
The British Library
Large national libraries, like The British Library, often collect grey literature, which they loan via their Document Supply Services

Academic conferences are events where people present news about their recent research and findings. Many conferences are held annually, sometimes at a different location each year. The conference organisers often collect the presented papers and publish them as the conference proceedings.

Web of Science
Web of Science indexes conference papers across STEM subjects (science, technology, engineering and medicine) and the social sciences from 1990 onwards. Each conference paper is accompanied by an abstract. You can access Web of Science through the Web of Knowledge portal.
Brunel Library's Conference Papers tab
Visit the Conferences Paper tab on the Managing and Sharing Information web page for further information on accessing print and full-text conference papers.

Contacting authors, peer groups and private companies can sometimes be a way of tracking down difficult to find grey literature. This can be done through:

written correspondence
email discussion lists
social networks, such as ResearchGate, Academia.edu and LinkedIn
If you are in health or social care, try CHAIN - Contact, Help, Advice and Information Network
NHS people may join NHS Networks - click on the Connect tab to find people with similar interests.

Theses often contain cutting-edge material. In many cases the information may not have made its way into published journal articles or books.

Brunel Library's Theses webpage
Visit the Theses webpage for further information on accessing Brunel, British, and International theses.

BASE
The Bielefeld Academic Search Engine (BASE) is a good place to search for grey literature. On the Advanced screen, you can opt to omit articles and thus focus on reports, theses etc.
BURA
Institutional repositories, such as BURA at Brunel University London, hold digital theses and research papers. You can search by keyword or browse by research area or collection.
OAIster
(Open Archives Initiative), pronounced oyster, claims to “find the pearls”. OAIster provides access to millions of digital resources at around 1,100 institutions - the majority are US organisations but British universities are also represented. Its coverage is multidisciplinary but “academically orientated”.
Opendoar
Opendoar (Directory of Open Access Repositories) is a global directory of open access academic repositories. You can use it to find repositories that match particular criteria, e.g. subject, content type and country.
OpenGrey
A multidisciplinary European database, which holds references to over 700,000 pieces of grey literature. In some cases you will be able to click through to the full text of a document or report

Since there are two accepted spellings, to locate information on gray/grey literature in general, search for: (gray OR grey) literature.

Most of the grey literature available on the Web is in the form of PDF documents so can save time by typing filetype:pdf after your keywords. Also consider restricting your search to the .org and/or .gov domains, e.g. type site:org after your search terms.

The Grey Literature Report in Public Health
A bimonthly publication of The New York Academy of Medicine alerting readers to new grey literature publications in health services research and selected public health topics.
Greynet
Grey Literature Network Service
The Kings Fund Library
The King's Fund's Information and Knowledge Services provide information on health and social care policy and management.
Mednar
Medical information

Why use grey literature?

Grey literature is an important source of information. To carry out a thorough search of the literature in your area it is essential to search for material which has not been published through commercial channels.

Though not always scholarly, it is produced by researchers and practitioners in the field. This may give you additional insight into working practice or allow you to develop current awareness from a non academic point of view.

It can often be produced more quickly, therefore being more current than other types of literature that have to go through a more formal review process. It may also be reporting on work in progress, for example conference literature may reflect ongoing research. This does mean that grey literature need additional scrutiny.

In addition, it can reduce positive publication bias - negative results are often reported in the grey literature but not in published work.