Grey Literature Searching for the Health Sciences

Grey literature is generally material and research produced by organizations outside of the traditional commercial  or academic publishing and distribution channels. For the health sciences grey literature can include government documents, clinical trials, dissertations, theses, materials in open depositories, and web pages. Organizations that produce grey literature can include government departments and agencies, non-governmental agencies, academic centers and departments, hospitals, associations or researchers.

It may be difficult to discover, access or evaluation grey literature since grey literature may be made available to the public or may only be distributed privately within an organization or group. 

There are several major indexes to doctoral dissertations. Not all Universities are covered by any one of these sources. To be thorough, all of them should be searched.