Using a unique dataset of 7479 respondents to the online Australian Sex Survey (July–September 2016), we explored factors relevant for individuals who self-identify as one of the many possible nonbinary gender options (i.e., not man or woman). Our results identified significant sex differences in such factors; in particular, a positive association between female height, higher educational levels, and greater same-sex attraction (female-female) versus a negative effect of lower income levels and more offspring. With respect to sex similarities, older males and females, heterosexuals, those with lower educational levels, and those living outside capital cities were all more likely to identify as the historically dichotomous gender options. These factors associated with nonbinary gender identification were also more multifaceted for females than for males, although our interaction terms demonstrated that younger females (relative to younger males) and nonheterosexuals (relative to heterosexuals) were more likely to identify as nonbinary. These effects were reversed, however, in the older cohort. Because gender can have such significant lifetime impacts for both the individual and society as a whole, our findings strongly suggest the need for further research into factors that impact gender diversity.
Read the full results of his study in Archives of Sexual Behaviour.