The National Institutes of Health (NIH) mandate to consider sex differences in both human and basic research (ie, “that scientists will account for the possible role of sex as a biological variable in vertebrate animal and human studies” (notice no. NOT‐OD‐15‐102) has led to renewed interest in studying potential hypotheses for sex differences in traits and diseases. Even though human studies of mental disorders have generally considered sex differences in etiologic and treatment studies, few basic studies of their underlying biology have investigated sex differences. The NIH mandate for inclusion of sex as a biological variable will help to align the findings from human and animal studies 1 and ultimately will assist in determining the etiology and treatment of mental disorders.
