Grey literature refers to any information source that is not commercially published. The definition of grey literature is evolving but it is generally defined as content that is produced and published by non-commercial private or public entities including pressure groups, charities and organisations. 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?
Why use grey literature?
Grey Literature adds another layer to your research and provides a different perspective thereby making your research more interesting. However, it is important to evaluate grey literature sources carefully by considering the credentials of the entity that produced the information as there may be inherent biases associated with the production of this information.
Below are some useful sites for finding grey literature. Some links will take you to databases which UCL Library Services subscribes to. These require that you authenticate with your UCL userID and password.
Google, Google Scholar and other search engines can also be useful to help you find grey literature.
Ovid PsycINFO is also a good source of psychology theses.
You can search trials registries to find the details of proposed, ongoing and completed clinical trials. Prioritise searching ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP) for systematic reviews where identifying clinical trials is important.