Grey Literature are information sources that are published outside of traditional, commercial publishing. In general, anything that is not a published journal article or book is probably grey literature. All of the following types of sources are examples of grey literature:
- Government policies, reports, and statistical data (such as reports from the CDC or AHRQ)
- Unpublished research
- Guidelines and protocols
- Clinical trials
- Conference posters and presentations
- YouTube videos, podcasts, blogs, informational webpages, and other social media posts