The Cochrane Handbook for Systematic Reviews of Interventions defines grey literature as "the kind of material that is not published in easily accessible journals or databases".
Search grey literature sources that make the most sense for your research question. These sources can include: materials and research produced by organizations outside of the traditional commercial or academic publishing, conference proceedings, dissertations, published reports or datasets and government documents.
The following sources are recommendations. If you are searching only for grey literature in databases, consider limiting your search by "publication type". Grey Literature can include technical reports, annual reports or government publications, etc.
|General Grey Literature Sources||Databases for Grey Literature|
|Google Scholar||Cochrane Library|
|World Health Organization||PsycINFO|
|Agency for Healthcare Research and Quality||Web of Science|
If you have trouble locating a dissertation, contact Wayne Shoaf at email@example.com or ph. 213-740-4090.
ProQuest Dissertations & Theses is also a good source for locating digitized dissertations produced at other universities in the United States.
In addition, more and more universities no longer require students to deposit their dissertations with ProQuest so you may want to search for an university's institutional repository via Google and search within that digital collection for a particular publication.
When searching for research studies that use a specific type of design or method, like quantitative, qualitative or quasi-experimental, you can have a more efficient and effective search by using some of the tips below to find these sources.
In some databases, you can search by methodology. For example, PsycINFO provides methodology as a limiter in their advanced search section:
For more details on PsycINFO, view this short tutorial.
If the database that you use does not have this option, you can enter the methodology that you are looking for as a keyword in your search. For example, if you are looking for experimental designs on the topic youth depression, you can enter search terms: "youth depression" AND "experimental design".
Note: Using quotation marks will search that exact phrase. However, you can also search without quotation marks. A phrase search (with quotations) will search that exact phrase and will narrow your search results. A good practice is to do multiple searches - modify your terms, find similar terms, do a search without quotation marks and do one with quotation marks (phrase searching).