Preferential publication of editorial board members in medical specialty journals

A Background: Publication bias and discrimination are increasingly recognised in medicine. A survey was conducted to determine if medical journals were more likely to publish research reports from members of their own than a rival journal's editorial board. Methods: A retrospective review was conducted of all research reports published in 2006 in the four competing medical journals within five medical specialties. Only three journals were willing to divulge the authorship of reports that had been rejected. Results: Overall, 4460 research reports were published in 2006 by the 20 journals from five subspecialties (mean 223 (SD=164) reports per journal; median 176; interquartile range 108-238). On average, 17.2 (7.7%) reports were from a journal's own editorial board (SD=10.7; median 15; interquartile range 10-23; n=20), and 6.3 (2.8%) reports were from a member of the editorial board of one of the three rival journals within the specialty (SD=7.3; median 3.5; interquartile range 1-8; n=60). There was a statistically significant excess of publications from the journal's own editorial board in 14 of the 20 journals (p < 0.05). Journals were almost three times more likely to publish reports from their own editorial board than from one of the three rivals within their subspecialty (p < 0.0001; median difference 11; Mann Whitney U test; power for 5% significance >99.99%). Conclusions: There was a significant excess of publications from medical journals' own editorial boards, although it is not possible to determine whether this is due to bias in the peer review process or selective submission by editors.