Occupational sex segregation is strongly predicted by psychological sex differences

Abstract If traits of individuals are associated with occupational choice, sex differences in those traits should be associated with sex differences in occupational choice, and consequently, with occupational sex segregation. In this cross-sectional study, we assessed the extent to which this is the case for spatial ability, verbal ability, agreeableness, emotional stability, interest in people and interest in things, across 429 occupations. Participants ( N = 2,576, aged 35–45) completed online tests and questionnaires, while students rated occupational requirements. For each occupation, the population sex composition of people with traits in line with requirements was estimated, using trait sex differences and occupational requirement profiles. Estimates were highly predictive of actual population sex ratios, with the model assessing interest and cognition in conjunction explaining the most variance ( R 2 = .49), followed by the interest model ( R 2 = .46) and the cognition model ( R 2 = .18). Among individual traits, sex differences in interest in things were by far the most predictive ( R 2 = .42). Notably, sex differences in cognition were more predictive of high proportions of men in occupations than high proportions of women. Given lifespan trait stability, these results suggest that cognition and interests matter in occupational choice, with sex differences consequently contributing substantially to occupational sex segregation.