Assessment of Health Disparities and Sexual Orientation Response Choices Used in Two US National Population-Based Health Surveys, 2020‒2021.

<strong>Objectives.</strong> To (1) compare responses to 2 survey questions designed to measure sexual orientation and (2) understand how variation in responses is associated with mental health. <strong>Methods.</strong> Data were from the National Longitudinal Study of Adolescent to Adult Health (Add Health) Sexual Orientation/Gender Identity, Socioeconomic Status, and Health Across the Life Course (SOGI-SES) study (2020-2021) in the United States. We used the adjusted Wald test to compare proportions of respondents who were (1) categorized as heterosexual or straight and sexual minorities using the sexual orientation questions designed for the Add Health study and the National Health Interview Survey (NHIS) and (2) diagnosed with depression or anxiety or panic disorder. <strong>Results.</strong> The Add Health question detected more than twice as many sexual minority respondents as the NHIS question. Those who responded as sexual minorities to the Add Health question but as heterosexual or straight to the NHIS question, primarily "mostly heterosexuals," had mental health outcomes that were more like those who were consistently classified as sexual minorities versus those consistently classified as heterosexual or straight. <strong>Conclusions.</strong> Current measures of sexual orientation in national-level surveys may underestimate the sexual minority population and sexual orientation‒related health disparities. <strong>Public Health Implications.</strong> Results illustrate the need for further research to expand measurement of sexual orientation on population-based health surveys. (<em>Am J Public Health</em>. 2024;114(12):1375-1383. https://doi.org/10.2105/AJPH.2024.307839).