Gray literature: An important resource in systematic reviews (pages 233–240)

Journal of Evidence-Based Medicine
August 2017  Volume 10, Issue 3  Pages 153–240
http://onlinelibrary.wiley.com/doi/10.1111/jebm.2017.10.issue-3/issuetoc

METHODOLOGY
Gray literature: An important resource in systematic reviews (pages 233–240)
Arsenio Paez
Version of Record online: 31 AUG 2017 | DOI: 10.1111/jebm.12266
Abstract
Systematic reviews aide the analysis and dissemination of evidence, using rigorous and transparent methods to generate empirically attained answers to focused research questions. Identifying all evidence relevant to the research questions is an essential component, and challenge, of systematic reviews. Gray literature, or evidence not published in commercial publications, can make important contributions to a systematic review. Gray literature can include academic papers, including theses and dissertations, research and committee reports, government reports, conference papers, and ongoing research, among others. It may provide data not found within commercially published literature, providing an important forum for disseminating studies with null or negative results that might not otherwise be disseminated. Gray literature may thusly reduce publication bias, increase reviews’ comprehensiveness and timeliness, and foster a balanced picture of available evidence.