Objectives: To examine the relationship between the amount of work involved for the systematic review (SR) team for each additional database searched in an SR versus the number of unique articles included in the final review that were retrieved from each additional database searched. Methods: We reviewed SRs and meta-analyses published in JAMA, Lancet, and Annals of Internal Medicine from January 2012 to December 2015, selecting those journals as high impact factor journals that have published over more than 50 SR…