Google Scholar provides a simple way to broadly search for scholarly literature. From one place, you can search across many disciplines and sources: articles, theses, books, abstracts and court opinions, from academic publishers, professional societies, online repositories, universities and other web sites. Google Scholar helps you find relevant work across the world of scholarly research.
Up to now we have concentrated on published sources of evidence, mainly as reported in journal articles and available in databases and other online sources.
Clinical colleagues and peers can be another source of evidence.
Don't forget that the process of evidence-based practice involves combining the best research evidence with clinical expertise. This clinical expertise might be your own, but also might be that of colleagues and peers with whom you work or associate.
Grey literature "refers to print or electronic literature that is produced by government, academia, business and industry, and is not controlled by commercial publishers ... i.e. where publishing is not the primary activity of the producing body." (ICGL Luxembourg definition, 1997. Expanded in New York, 2004.)
Grey literature does not form a part of traditional publishing, and is not widely disseminated. It can include a huge range of resources form theses and dissertations, through conference proceedings, government documents, and research reports to digital repositories and registers of clinical trials.