Grey Literature refers to non-traditional sources of information and may include: reports, leaflets, bulletins, dissertations etc. These sources of information may not be published through the traditional route and may not be available within typical bibliographic databases. Often, these materials are not peer-reviewed unlike journal articles.
Fig 1 shows the process of searching for grey literature sources.
Fig 1: Process of grey literature search. Adapted from: Duffield, A. et al. (2004). "Process to Identify the Grey Literature", Review of the published literature for the impact and cost-effectiveness of six nutrition related emergency interventions
Alberani, V et al. (1990). The use of grey literature in health sciences: a preliminary survey. Bulletin of the Medical Library Association. 78(4): 358-63.
There are a number of sources where grey literature can be found. These include:
The Internet is now a major source to retrieve grey literature and often a good starting point to research a particular topic area. Please check the links below:
Relevant to all
You can also refer to our A to Z list of identified grey literature websites on the right column of this page. As your work progresses, you’ll become aware of the main organisations active in the medical/healthcare specialty. E.g. government bodies and research institutes. Do a thorough search of their webpages and articles/published works.
Here are some databases from our NTU library website that index conference papers and conference proceedings:
1) Web of Science
3) ProQuest Dissertation & Theses Global (PQDT Global) & ProQuest Dissertations &Theses – UK and Ireland (Index to Theses)*
6) TRIP Database (clinical medicine) – (Click here)
The AACODS technique to enable evaluation and critical appraisal: