Medicine & Dentistry

Grey literature refers to any information source that is not commercially published. As these sources are dispersed and not collected by centralised publishing platforms, they are sometimes difficult to find and can be tiresome to search. 

What counts as grey literature?

• Internal reports, such as government white papers
• Meeting minutes and notes
• Conference abstracts, papers
• Theses and dissertations
• Pre-print or unpublished research
• Clinical trial data
• Patents and technical standards information, such as British Standards (BSO) or International Standards (ISO)

Why use grey literature?

• Often good quality information produced by experts in their field, e.g. white papers are commissioned by the government from a body of subject specialists
• Providing important insights into the 'reality' of research, e.g. clinical trial data that is not published because the study was not successful and therefore not commercially beneficial
• Reflects the expertise of individuals not associated with academia e.g. independent think tanks; charities representing oppressed groups or individuals; other industry experts (for example, in business or technology).

"Standards are agreed ways of doing something, written down as a set of precise criteria so they can be used as rules, guidelines or definitions."  (BSI)

Bibliographic databases sometimes include conference papers such as abstracts or proceedings. Some databases covering health / biomedical topics which include conference papers include:

Depending on the topic of your research, it is sometimes useful to search for reports or other literature produced by charities or organizations. A few examples are listed below but there are likely to be others specialised in your area of interest.

Searching the internet is not recommended as a method of finding authoritative scholarly sources for your work. However, there are circumstances where you might need to use a general search engine such as Google, for example if you are looking for grey literature or some very basic background information about a topic.

It is crucial that you carefully evaluate the information you find on the web, before deciding whether to use it to inform your work. See our guide to Evaluating information.

Search engines operate very differently to bibliographic databases and are not designed for structured searching. However there are some simple tools you can use if needed, to carry out a search more effectively. See Google's page about refining web searches using Google and how to do an advanced search.

Google can be used to carry out a broad search for documents or web pages from a specific domain. This could be useful if, for example, you wanted to find literature about a specific topic from any website of the NHS, or any website of the UK government.

To achieve this, search with site: followed by the domain, e.g. site:.nhs.uk

Make sure there is no space between the site: and the domain

Using Google's Advanced Search gives you more options. Please note however that Google does not function in the same way as a bibliographic database and tools such as truncation, adjacency etc are not supported. See Google's page about refining web searches using Google and how to do an advanced search.