Study concept and design: von Elm, Marušić.
Acquisition of data: all authors.
Analysis and interpretation of data: all authors.
Drafting of the manuscript: all authors.
Critical revision of the manuscript for important intellectual content: all authors.
Statistical analysis: Malički.
Administrative, technical, and material support: Malički, Marušić.
Study supervision: von Elm, Marušić.
Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Drs Marušić and von Elm are members of the Advisory Board of the Seventh International Congress on Peer Review and Biomedical Publication.
Previous Presentation: This study was presented at the Seventh International Congress on Peer Review and Biomedical Publication, Chicago, Illinois, September 8-10, 2013.
Additional Contributions: We thank the Esteve Foundation for organizing a Discussion Group on Editorial Research in Barcelona (Catalonia, Spain) on December 12-13, 2012, which gave us the idea for the study. We thank Annette Flanagin, RN, MA, and Drummond Rennie, MD, at JAMA for providing access to the abstracts and JAMA articles from the early Peer Review Congresses, for which they were not compensated.