Positive outcome bias in peer review of journal submissions

January 01, 0001

Positive outcome bias in peer review of journal submissions

If positive-outcome bias exists, it threatens the integrity of evidence-based medicine. These US authors sought to determine whether positive- outcome bias is present during peer review by testing whether peer reviewers would (1) recommend publication of a "positive" version of a fabricated manuscript over an otherwise identical "no-difference" version, (2) identify more purposefully placed errors in the no-difference version, and (3) rate the "Methods" section in the positive version more highly than the identical "Methods" section in the no-difference version. Two versions of a well- designed randomized controlled trial that differed only in the direction of the finding of the principal study end point were submitted for peer review to 2 journals in 2008-2009. Of 238 reviewers for The Journal of Bone and Joint Surgery and Clinical Orthopaedics and Related Research randomly allocated to review either a positive or a no-difference version of the manuscript, 210 returned reviews.

They found: "Reviewers were more likely to recommend the positive version of the test manuscript for publication than the no-difference version (97.3% vs 80.0). Reviewers detected more errors in the no-difference version than in the positive version (0.85 vs 0.41). Reviewers awarded higher methods scores to the positive manuscript than to the no-difference manuscript (8.24 vs 7.53), although the ‘Methods’ sections in the 2 versions were identical."

The authors concluded: "Positive-outcome bias was present during peer review. A fabricated manuscript with a positive outcome was more likely to be recommended for publication than was an otherwise identical no- difference manuscript."

These are eye-opening and concerning findings.

For the full abstract, click here.

Arch Intern Med 170(21):1934-1939, 22 November 2010
© 2010 to the American Medical Association
Testing for the Presence of Positive-Outcome Bias in Peer Review-A Randomized Controlled Trial. Gwendolyn B. Emerson, Winston J. Warme, Fredric M. Wolf, James D. Heckman, Richard A. Brand, Seth S. Leopold. Correspondence to Dr.Leopold: [email protected]

Category: HSR. Health Services Research. Keywords: publication bias, peer review, evidence-based medicine, randomized controlled trial, journal watch.
Synopsis edited by Dr Linda French, Toledo, Ohio. Posted on Global Family Doctor 14 December 2010

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