Answered By: Valerie Weis Last Updated: Jun 10, 2019 Views: 858
Articles in a peer-reviewed or "refereed" journal are reviewed prior to publication by experts (usually faculty members) with credentials in the article's field of study. Many Harvard article databases allow you to limit your search results to only include peer-reviewed journals.
Other material like white papers and policy briefs that are not peer-reviewed can still be valuable for your literature review. Relevant preprints that will eventually be peer-reviewed or gray literature unlikely to be published in a journal should be included as long as they pass the C.R.A.A.P. test, evaluating Currency, Relevancy, Authority, Accuracy, and Purpose.
A good strategy for finding gray literature is to conduct a search in the HKS Library Customized Google Think Tank search, which includes over 700 think tank sites from across the world.