N. Xiao1, N. Mansukhani1, D. Fregolente2, M. Kibbe1,3 1Northwestern University,Department Of Surgery,Chicago, IL, USA 2Northwestern University,Department Of Chemical And Biological Engineering,Chicago, IL, USA 3University Of North Carolina At Chapel Hill,Department Of Surgery,Chapel Hill, NC, USA
Introduction:
Previous studies have demonstrated that sex bias exists in surgical research. Females are underrepresented as research subjects and as investigators in surgical scientific research. We aimed to investigate the effect of author gender on sex-bias in surgical research, and to explore whether investigators benefit from performing sex-inclusion research. We hypothesized that author gender impacts sex-bias.
Methods:
Data were abstracted from 1,921 original, peer-reviewed articles published from 01/01/11-12/31/12 in 5 general-interest surgery journals. Excluded were articles that pertained to a sex-specific disease, did not report the number of subjects, or contained gender ambiguous author names. Abstracted data included gender of the first and last author, number of female and male subjects included in each study, surgical specialty, and number of citations received per article. Quantification of sex bias was performed by examining the inclusion of male and female subjects and sex-matching of included subjects. Further analysis of the presence of sex-based reporting of data, sex-based statistical analysis of data, and sex-based discussion of the data was included.
Results:
Of the 1,802 articles included in this study, a total of 2,791 (77.4%) first and last authors were male. 70.3% of first authors and 84.6% of last authors were male. The prevalence of male authors was consistent across all five journals and among both clinical and basic science research (p=NS). Investigations in breast, endocrine, and surgical education were conducted by more female investigators compared to other specialties (p<0.05). Female authors recruited a higher median number of female subjects compared to their male counterparts (p=0.01), but sex-matched the inclusion of subjects less frequently. There were no differences between male and female authors in sex-based reporting, sex-based statistical analysis, and sex-based discussion of the data, nor the number of citations received. However, studies which performed sex-based reporting yielded 2.8 more citations (95% CI 1.2 – 4.4, P<0.01), studies which performed sex-based statistical analysis yielded 3.5 more citations (95% CI 1.8 – 5.1, P<0.01), and studies containing a sex-based discussion of the data yielded 2.6 (95% CI 0.7 – 4.5, P<0.01) more citations compared to studies which did not report, analyze, or discuss data by sex. Articles with higher percent sex matching of subjects also received more citations, with an increase of 1 citation per 4.8% (95% CI 2.0 – 7.7%, P<0.01) increase in percent of sex matching.
Conclusion:
Sex bias in surgical research is prevalent among both men and women authors. However, women authors include proportionally more female subjects in their studies compared to male authors. Lastly, studies which address sex bias received significantly more citations.