Types of Information Sources
Grey Literature
What is Grey Literature?
GreyNet International (2024) state that grey literature comprises
“multiple document types produced on all levels of government, academics, business, and organization in electronic and print formats not controlled by commercial publishing i.e. where publishing is not the primary activity of the producing body.”
The term grey literature thus encompasses a wide variety of material in a variety of formats. Some examples of grey literature that you might include in your literature review are:
- Websites, publications and reports produced by bodies such as governments (i.e. Dept of Health, Dept of Education etc – policy documents, reports and other resources), research institutes, non-profit and professional organisations (ie APA.. – publications, conferences, annual reports, resources)
- Theses and dissertations
- Conference proceedings (Proceedings consist of a selection of the papers presented at the conference)
- Research reports, including research in progress
- Datasets
- Statistics
- Market reports
- Clinical trials registries
Searching for grey literature will likely involve the use of a search engine (such as Google), so it vital that you evaluate sources before including them in your research.
Considering grey literature as a source for your review is important because:
It can help avoid publication bias
- It can provide a more rounded overview of your area of focus – viewpoints not explicitly represented in published literature. May also offer a local viewpoint.
- Grey literature may be more timely that formally published reports or articles as it has not spent time going through the publishing process
- It can provide more detailed insights – not subject to the very strict word count of journal articles.
Key Takeaways
However do remember:
- Evaluate carefully those sources you find on the internet
- Grey literature is not subject to peer review
- It can be tricky to know where to look for relevant grey information.
