Skip to Main Content

PSYD98: Thesis in Psychology

A guide for advanced research projects and supervised studies for psychology students.

What Is Grey Literature?

Grey Literature is any literature that has not been published through traditional means. It is often excluded from large databases and other mainstream sources (e.g. academic journals). Grey literature can also mean literature that is hard to find or has inconsistent or missing bibliographic information. 

Search grey literature to:

  • avoid bias
  • ensure that a review is as thorough as possible
  • find sources for negative results or brand new evidence
  • discover more references to published literature that your database search might have missed

Additional resources are available through Gerstein Library's Grey Literature page.

Effective Web Searching

There is no control over the content that is published on the internet.

Before you conduct research, you should become familiar with strategies to effectively evaluate the information you find while searching the web.

Decoding Domains

Commonly recognized top-level domains:

  • .edu = educational site (usually a university or college)
  • .com = commercial business site
  • .gov = U.S. governmental/non-military site
  • .mil = U.S. military sites and agencies
  • .net = networks, internet service providers, organizations
  • .org = U.S. non-profit organizations and others

Examples of Internet country code top-level domains:

  • .ca = Canadian site
  • .uk = United Kingdom site


Search Google

Before searching Google, take a look at the Google Search Strategies video in box above to learn some useful web search tips.

Google Web Search

Evaluating Grey Literature

The AACODS checklist is a great tool to evaluate and critically appraise grey literature:

infographic of the six categories that make up the AACODS checklist

James Cook University Library. (n.d.). [PNG image of the six categories that make up the AACODS checklist]. Retrieved September 23, 2021, from