Background. In Japan, gender inequality between males and females in the medical profession still exists. We examined gender gaps in surgeons' incomes.
Methods. Among 8,316 surgeons who participated in a 2012 survey by the Japan Surgical Society, 546 women and 1,092 men within the same postgraduation year were selected randomly with a female-to-male sampling ratio of 1:2 (mean age, 36 years; mean time since graduation, 10.6 years).
Results. Average annual income was 9.2 million JPY for women and 11.3 million JPY for men (P < .0001). A general linear regression model showed that the average income of men remained 1.5 million JPY greater after adjusting for gender, age, marital status, number of children, number of beds, current position, and working hours (Model 1). In Model 2, in which 2 statistical interaction terms between annual income and gender with marital status and number of children were added together with variables in Model 1, both interactions became significant, and the gender effect became nonsignificant. For men, average annual income increased by 1.1 million JPY (P < .0001) when they were married and by 0.36 million JPY per child (P = .0014). In contrast, for women, annual income decreased by 0.73 million JPY per child (P = .0005).
Conclusions. Male surgeons earn more than female surgeons, even after adjusting for other factors that influenced a surgeon's salary. In addition, married men earn more than unmarried men, but no such trend is observed for women. Furthermore, as the number of children increases, annual income increases for men but decreases for women.