Project Summary More than 8 million women in the US identify as a sexual minority- including lesbian, gay, bisexual, or queer, yet the health needs of this population remain understudied. Studies show sexual minority women are less likely to receive routine preventive care, including cancer screening. Studies of breast and cervical cancer risk among sexual minority women are mixed, with higher prevalence of risk factors including smoking, alcohol use, and obesity, but lower prevalence of risk factors such as HPV infection and use of hormonal contraceptives. As no national cancer registries collect information on sexual identity, we have no population-level estimates of cancer burden among sexual minority women and are unable to accurately evaluate disparities or prioritize interventions to improve low screening rates. We propose to first characterize existing sexual identity disparities in cervical cancer screening uptake using a structural equation modeling approach (Aim 1). This approach will evaluate the extent to which previously described disparities in screening uptake are mediated by differences in care access, prevalence of cancer risk factors, or both. We will then incorporate these data into a simulation model of cancer progression to produce feasible estimates of cervical cancer incidence and mortality by stage among sexual minority women (Aim 2). Finally, we will repeat the application of this full framework to assess relevant mediators of breast cancer screening and update the existing model to reflect our understanding of breast cancer natural history to estimate incidence and mortality among sexual minority women (Aim 3). My career to date has focused on using econometric and simulation modeling to better understand and address gaps in cervical cancer prevention among traditionally underserved populations. My ultimate goal is an independent research career focusing on effective strategies to reduce cancer health inequities among sexual and gender minority individuals. This award will allow her to take the next step in her career, building on her background in health equity and decision modeling while facilitating her training in causal epidemiology approaches, breast cancer epidemiology, and the health needs of sexual minority women. Dr. Spencer's training plan draws on the extensive methodological expertise of her mentorship team and the exceptional educational and professional resources at Dell Medical School. The overall goal of this work is to improve the health of sexual minority women through characterizing multilevel sources of inequities in breast and cervical cancer screening, incidence, and mortality.