The association between physician sex and patient outcomes: a systematic review and meta-analysis

Background: Some prior studies have found that patients treated by female physicians may experience better outcomes, as well as lower healthcare costs than those treated by male physicians. Physician–patient sex concordance may also contribute to better patient outcomes. However, other studies have not identified a significant difference. There is a paucity of pooled evidence examining the association of physician sex with clinical outcomes. Methods: This random-effects meta-analysis was conducted according to the PRISMA guidelines and prospectively registered on PROSPERO. MEDLINE and EMBASE were searched from inception to October 4th, 2023, and supplemented by a hand-search of relevant studies. Observational studies enrolling adults (≥ 18 years of age) and assessing the effect of physician sex across surgical and medical specialties were included. The risk of bias was assessed using ROBINS-I. A priori subgroup analysis was conducted based on patient type (surgical versus medical). All-cause mortality was the primary outcome. Secondary outcomes included complications, hospital readmission, and length of stay. Results: Across 35 (n = 13,404,840) observational studies, 20 (n = 8,915,504) assessed the effect of surgeon sex while the remaining 15 (n = 4,489,336) focused on physician sex in medical/anesthesia care. Fifteen studies were rated as having a moderate risk of bias, with 15 as severe, and 5 as critical. Mortality was significantly lower among patients of female versus male physicians (OR 0.95; 95% CI: 0.93 to 0.97; P_Q = 0.13; I² = 26%), which remained consistent among surgeon and non-surgeon physicians (P_interaction = 0.60). No significant evidence of publication bias was detected (P_Egger = 0.08). There was significantly lower hospital readmission among patients receiving medical/anesthesia care from female physicians (OR 0.97; 95% CI: 0.96 to 0.98). In a qualitative synthesis of 9 studies (n = 7,163,775), patient-physician sex concordance was typically associated with better outcomes, especially among female patients of female physicians. Conclusions: Patients treated by female physicians experienced significantly lower odds of mortality, along with fewer hospital readmissions, versus those with male physicians. Further work is necessary to examine these effects in other care contexts across different countries and understand underlying mechanisms and long-term outcomes to optimize health outcomes for all patients. Review registration: PROSPERO – CRD42023463577.