Sex Representation among Principal Investigators in Cardiac Surgery Clinical Trials in the United States: The Glass Ceiling and Room for Improvement

Objective: The aim of this study was to determine the sex representation among principal investigators (PIs) in US cardiac surgery clinical trials. Summary Background Data: Being a principal investigator in a US clinical trial confers national recognition among peers. Sex representation among principal investigators (PIs) in US cardiac surgery clinical trials has not been evaluated. Methods: We evaluated 124 US cardiac surgery trials registered on Clin-icalTrials.gov from 2014 to 2019. Sixty trials included PIs (n = 266) from 128 institutions that had a combined total of 1040 adult cardiac surgeons. We examined sex representation among junior-level (instructor or assistant professor) and senior-level (associate, full, or Emeritus professor) PIs by calculating the participation-to-prevalence ratio (PPR), whereby a PPR range of 0.8 to 1.2 reflects equitable representation. Results: The pool representation percentage was 6.1% (63/1040) for women and 93.9% (977/1040) for men. A total of 266 PI positions were assigned to adult cardiac surgeons: 6 (9.5%; PPR = 0.37) from the female pool and 260 (26.6%; PPR = 1.04) from the male pool (P = 0.004). The percentage of PIs with studies funded by industry was 9.5% ofthe female pool (PPR = 0.39) and 25.0% of the male pool (PPR = 1.04) (P = 0.009). No National Institutes of Health-funded or other funded trials had female PIs. An overall trend was observed toward disproportionally more men than women among PIs, especially at the senior level (P = 0.027). Conclusions: Equitable opportunities for PI positions are available for junior-level but not senior-level cardiothoracic surgeons. These results suggest a need for active engagement and promotion of equal opportunities in cardiac surgery.