Health research on trans* and intersex populations prompts essential questions about how researchers use sex as a biological variable. According to the NIH policy, “NIH expects that sex as a biological variable will be factored into research designs, analyses, and reporting in vertebrate animal and human studies” (“NIH Policy”). The NIH policy was developed to set right the androcentric history of biomedical research and advocate for the inclusion of women in clinical trials. However, this policy raises concerns for any research on trans* and intersex individuals since sex as a biological variable is often collected as a binary (M/F) sex assigned at birth.
We look to Sarah Richardson’s concept of sex contextualism to problematize current approaches to sex in research and to develop a harm-reduction approach to sex data usage. Sex contextualism is simply the “view that the definition of sex and sex-related variables, and whether they are relevant in biomedical research, depends on the research context” (9). Richardson asserts that, in research, we should adopt an ameliorative notion of sex, one that considers what we intend to achieve with sex as a research variable. By viewing sex as a multifaceted variable, sex contextualism provides a possible solution to current binary uses of sex data in health research that create epistemological harm for trans* and intersex folks. A sex contextualist approach to sex data pays attention to the multitude of ways sex can be defined and allows for a more nuanced understanding of gender, sex, and identity in health research.
- Sex Contextualism
Richardson explains how using non-contextualized binary sex as a biological variable prompts the danger of overgeneralizing the meaning of sex and supporting essentialist notions of sex. In other words, simply including binary sex as a research variable does not mean that we can make conclusions about the impact of sex on other research factors or make sweeping claims about the importance of sex difference. Sex includes a bundle of different variables, including sex hormones, gonads, genitalia, and secondary sex characteristics, all of which can interact differently with other biological variables. Accordingly, sex as a biological variable without context does not provide accurate health information for research on cisgender endosex populations, much less the more complicated needs of trans* and intersex folks.
Take, for instance, the impact of gender-affirming hormone therapy (GAHT) on a transgender woman’s risk of breast cancer. While transgender women have lower rates of breast cancer risk compared to cisgender women, their risk remains significantly higher than that of cisgender men (Vasilev et al.). Ignoring the impact of gender-affirming hormone therapy (GAHT) in transgender women would hinder the study of breast cancer and the role of sex hormones in breast health. Laboratory practices should treat sex as it in functions in lived reality, meaning sex should be conceived as a “complex, multifaceted, and contextualized variable, in which different aspects of biological sex become differently relevant at different times, depending on questions, populations, and analytical strategies” (Shattuck-Heidorn and Ichikawa).
The NIH’s current policy on sex as a biological variable needs further consideration to reduce potential harm done to trans* and intersex folks in health research. With this in mind, we extend Richardson’s argument to focus on trans* and intersex individuals to show how sex contextualism is a necessary framework for health research.
- Sex Data in Research
Sex data needs more careful consideration in biomedical research. Non-contextualized binary sex as a biological variable fails at each level of data usage: (1) Data collection (2) Data interpretation (3) Data presentation. These failures of data usage for trans* and intersex individuals often take the form of sex slippage and sex confusion:
the frequent substitution of sex and sex-related terms for gender, and vice versa, often reflecting an underlying assumption of the concordance of sex and gender
the fact that any given sex variable holds many different potential meanings, from sex assigned at birth to current sex for purposes of health insurance, and may or may not correspond to the presence of any particular body part or hormonal status. (Albert and Delano 3)
Sex/gender slippage during data collection occurs for multifaceted reasons. Researchers may misclassify someone as cisgender despite their transitioning status, and intake questionnaire vagueness may blur the lines between “sex” and “gender.” This confusion often leads to inaccurate data collection, especially for trans* and intersex individuals.
Data interpretation introduces another layer of potential misapprehension, with far-reaching consequences. Misclassifying a transgender woman on GAHT as male can yield misleading results, potentially affecting study validity, especially when studies involve sex hormones. A transgender woman’s sex hormones are no different than her cisgender counterpart.
Sex confusion can pervade data interpretation as well, as many forget sex assigned at birth only considers genitalia, disregarding more accurate sex characteristics, such as sex genes and sex hormones. This oversight can lead to generalized conclusions, illustrated by Zhao et al.’s analysis of Ambien clinical research that a constructed “sex-difference fact” (488).
Even at the data presentation stage, sex confusion and misclassification persist. Making broad claims about “women” based on a single sex hormone can result from this error. By overgeneralizing all biological variables as “sex,” researchers may inadvertently indulge in sex obsession, as described in the work of Albert et al. In response to these persistent challenges, it is evident that novel approaches to handling sex data in research are imperative.
- Sex Contextualist Solution
To address these challenges, comprehensive data collection is vital for intersex and trans* individuals. We should shift from binary sex classification and, instead, document all relevant sex characteristics. Contextual data presentation and interpretation are equally essential. For instance, recognizing a transgender woman’s female sex hormones may provide a more accurate picture of her health and better informs research conclusions. Without acknowledging sex and its context, we risk neglecting critical health-related details.
Based on the complexity of sex and its contexts, we suggest that researchers consider the following variables for data collection, interpretation, and representation. As sex contextualists, we should remember that each of these depends on the research study context:
- Secondary sex characteristics: Sex hormones, body fat distribution, breast tissue, etc.
- Gender Identity
- Gender-affirming medication or surgery
- The date that the data is collected: sex data can change with time (e.g. people can go under GAHT and/or surgeries after data collection)
Advocating for sex contextualism is essential for achieving just, inclusive, and accurate research practices for trans*, intersex, and cisgender folks alike. Sex contextualist research practices would require researchers to behave more accurately with sex data, ultimately creating a more equitable culture of health for trans* and intersex communities.
Albert, Kendra, and Maggie Delano. “Sex Trouble: Sex/Gender Slippage, Sex Confusion, and Sex Obsession in Machine Learning Using Electronic Health Records.” Patterns, vol. 3, no. 8, 2022.
“NIH Policy on Sex as a Biological Variable.” National Institutes of Health, https://orwh.od.nih.gov/sex-gender/nih-policy-sex-biological-variable. Accessed 15 November 2023.
Richardson, Sarah S. “Sex Contextualism.” Philosophy, Theory, and Practice in Biology, vol. 14, 2022.
Shattuck-Heidorn, Heather and Kelsey Ichikawa. “No Sex Without Context: A Q&A with Sarah Richardson on ‘Sex Contextualism.’” Gendersci Lab, 12 Apr. 2022, https://www.genderscilab.org/blog/q-and-a-sarah-richardson-on-sex-contextualism.
Vasilev, Dzhuliyan V., et al. “Breast Cancer Screening in Transgender Women.” Journal of Women’s Health, 2023.
Zhao, Helen, et al. “Making a ‘Sex-Difference Fact’: Ambien Dosing at the Interface of Policy, Regulation, Women’s Health, and Biology.” Social Studies of Science, 2023, p. 03063127231168371.
 We are using “trans*” as an umbrella term for transgender, genderqueer, non-binary, and other gender-diverse individuals. Generally, we are referring to anyone whose gender does not align with sex assigned at their birth.
 The list of variables we provide can be adjusted for biological considerations of sex and is not a fixed list.