Considering Sex and Gender in Epidemiology: a Challenge Beyond Terminology – Methodological Research

BackgroundEpidemiologists need tools to measure effects of gender, a complex concept originating in the humanities and social sciences which is not easily operationalized in the discipline. MethodsWe conducted a conceptual analysis and applied causal and mediation analysis methodology to standard questions in order to propose a methodologically appropriate strategy for measuring sex and gender effects in health.ResultsWe define gender as a set of norms prescribed to individuals according to their attributed-at-birth sex. Gender pressure creates a systemic gap, at population level, in behaviors, activities, experiences, etc. between men and women. A pragmatic individual measure of gender would correspond to the level at which an individual complies with a set of elements constituting femininity or masculinity in a given population, place and time. However, defining and measuring gender is not sufficient to isolate the effects of sex and gender on a health outcome. We should also think in terms of pathways to define appropriate analysis strategies. Gender could also be examined as a mechanism rather than through its realization in the individual, by considering it as an interaction between sex and environment. ConclusionsBoth analytical strategies have limitations relative to the impossibility of reducing a complex concept to a single or a few measures, and of capturing the entire effect of the phenomenon. However, these strategies could lead to more accurate and rigorous analyses of the mechanisms underlying health differences between men and women, and ultimately limit the sex and/or gender bias encountered in epidemiological and clinical research studies.