Association between anaesthesia–surgery team sex diversity and major morbidity

Background — Team diversity is recognized as not only an equity issue but also a catalyst for improved performance through diversity in knowledge and practices. However, team diversity data in healthcare is limited and whether it may affect outcomes in surgery is unknown. We examined the association between anesthesiology-surgery team sex-diversity and post-operative outcomes.

Methods — We conducted a population-based retrospective cohort study of adults undergoing major inpatient surgeries over 2009-2019. The exposure was the hospital percent of female anesthesiologists and surgeons in the year of surgery. The outcome was 90-day major morbidity. Restricted cubic splines identified a clinically meaningful dichotomization of team sex-diversity into lower and higher diversity at >35% female anesthesiologists and surgeons. The association with outcomes was examined using multivariable logistic regression.

Results — Of 709,899 index surgeries performed at 88 hospitals, 90-day major morbidity occurred in 14.4%. The median proportion of female anesthesiologists and surgeons per hospital per year was 28% (absolute range: 25-31%). Care in hospitals with higher sex-diversity (>35% female) was associated with reduced odds of 90-day major morbidity (OR 0.97, 95%CI 0.95-0.99; p 0.02) after adjustment. The magnitude of this association was greater for patients treated by female anesthesiologists (OR 0.92, 95%CI 0.88-0.97; p 0.002) and female surgeons (OR 0.83, 95%CI 0.76-0.90; p <0.001).

Conclusion — Care in hospitals with higher anesthesiology-surgery team sex-diversity was associated with better post-operative outcomes. Care in a hospital reaching a critical mass of >35% female anesthesiologists and surgeons was associated with 3% lower odds of 90-day major morbidity.