EFFECT ON THE QUALITY OF PEER-REVIEW OF BLINDING REVIEWERS AND ASKINGTHEM TO SIGN THEIR REPORTS - A RANDOMIZED CONTROLLED TRIAL

Context.-Anxiety about bias, lack of accountability, and poor quality of peer review has led to questions about the imbalance in anonymity b etween reviewers and authors, Objective.-To evaluate the effect on the quality of peer review of blinding reviewers to the authors' identiti es and requiring reviewers to sign their reports. Design.-Randomized c ontrolled trial. Setting.-A general medical journal. Participants.-A t otal of 420 reviewers from the journal's database, Intervention.-We mo dified a paper accepted for publication introducing 8 areas of weaknes s. Reviewers were randomly allocated to 5 groups. Groups 1 and 2 recei ved manuscripts from which the authors' names and affiliations had bee n removed, while groups 3 and 4 were aware of the authors' identities. Groups 1 and 3 were asked to sign their reports, while groups 2 and 4 were asked to return their reports unsigned. The fifth group was sent the paper in the usual manner of the journal, with authors' identitie s revealed and a request to comment anonymously. Group 5 differed from group 4 only in that its members were unaware that they were taking p art in a study. Main Outcome Measure.-The number of weaknesses in the paper that were commented on by the reviewers. Results.-Reports were r eceived from 221 reviewers (53%). The mean number of weaknesses commen ted on was 2 (1.7, 2.1, 1.8, and 1.9 for groups 1, 2, 3, and 4 and 5 c ombined, respectively). There were no statistically significant differ ences between groups in their performance. Reviewers who were blinded to authors' identities were less likely to recommend rejection than th ose who were aware of the authors' identities (odds ratio, 0.5; 95% co nfidence interval, 0.3-1.0), Conclusions.-Neither blinding reviewers t o the authors and origin of the paper nor requiring them to sign their reports had any effect on rate of detection of errors, Such measures are unlikely to improve the quality of peer review reports.