Disequilibrium in Gender Ratios among Authors who Contributed Equally

Abstract

In recent decades, the biomedical literature has witnessed an increasing number of authors per article together with a concomitant increase of authors claiming to have contributed equally. In this study, we analyzed over 3000 publications from 1995-2017 claiming equal contributions for authors sharing the first author position for author number, gender, and gender position. The frequency of dual pairings contributing equally was male-male > mixed gender > female-female. For mixed gender pairs males were more often at the first position although the disparity has lessened in the past decade. Among author associations claiming equal contribution and containing three or more individuals, males predominated in both the first position and number of gender exclusive groupings. Our results show a disequilibrium in gender ratios among authors who contributed equally from expected ratios had the ordering been done randomly or alphabetical. Given the importance of the first author position in assigning credit for a publication, the finding of fewer than expected females in associations involving shared contributions raises concerns about women not receiving their fair share of expected credit. The results suggest a need for journals to request clarity on the method used to decide author order among individuals claiming to have made equal contributions to a scientific publication.