Incidence and nature of unblinding by authors: Our experience at two radiology journals with double-blinded peer review policies

OBJECTIVE. The purpose of our study was to prospectively determine the incidence and nature of unblinding by authors as to their identities or institutions in their submission of original major manuscripts to two radiology journals with double-blinded peer review policies. MATERIALS AND METHODS. The editors of two radiology journals reviewed 880 major original manuscripts submitted to their journals during a 6-month period without knowledge of the identities and institutions of the authors. Each manuscript was inventoried for possible author or institutional unblinding and for the specific types of unblinding violations. RESULTS. Of 880 manuscripts, 300 (34%) contained information that potentially unblinded the identities of the authors, their institutions, or both. The editors correctly identified the authors or institutions in 221 (74%) of the 300 manuscripts, which represented 25% of the total manuscripts. The most frequent unblinding violations were statement of the authors' initials within the manuscript, referencing work "in press," identifying references as the authors' previous work, and revealing the identity of the institution in the figures. CONCLUSION. Despite explicit instructions to authors, 34% of 880 prospectively evaluated manuscripts submitted to two radiology journals contained information that potentially or definitely unblinded the identities of the authors or their institutions.