LAUSR

Sex and gender are fundamental drivers of health.1–3 While not mutually exclusive, the terms sex and gender are often (incorrectly) used interchangeably.4 Sex is a biological variable that defines humans (and other species) as male and female (or intersex) according to their reproductive organs and functions, based on chromosomal assignment. The term sex differences should be used to describe sex-related biological or physiological differences between males and females. By comparison, gender is a socially constructed variable that refers to the roles, behaviours, activities and attributes that a given society, at a given time, considers appropriate for men and women. At present, there is no consensus on the measurement of gender, as gender identity, roles and norms vary considerably across settings and over time.5 6 Nevertheless, methods to measure gender are in development and recognise that gender both operates on a continuum and can change over time. In light of the above, it could be argued that knowledge of both sex at birth and gender identity should be reported in health research.5 Historically, there has been a tendency to understate or misunderstand the role of sex and especially gender in health and medicine.1 3 Sex and gender dimensions of health were often considered as solely being relevant to the health needs specific to women and men, such as sexual and reproductive (including maternal) health issues. For many years, therefore, women were not included in research studies of diseases affecting both sexes, as it was assumed that any research findings, although based on studies of men only, would be relevant for both women and men.1–3 7 This has led to a failure to identify and address sex-specific and gender-specific determinants of health, including those that drive the greatest burden of ill health …