Grey Literature: Its Emerging Importance

This article emphasizes the importance of grey literature in the arsenal of search tools available to medical researchers. Because of the delay between research and publication, and because of the potential that some important research may never be published, access to innovative information is challenging. Grey literature is a tool to fill that void. The authors define grey literature, explore its sources, and identify its major users and uses. The authors identify the range of grey literature, its advantages and disadvantages, the various outlets that produce it, and where it may be found.