DESCRIPTION (provided by applicant): HIV/AIDS is one of the leading infectious diseases worldwide and has a particularly significant impact in developing countries in Sub-Saharan Africa in terms of disease and economic burden. Social determinants, including structural, community, and health systems-level factors, can have significant impact on the prevention and successful treatment of HIV, influencing individuals' behaviors around taking risks, getting tested for HIV, entering into care, being retained in care and adhering to medication long-term. However, most prior studies of social determinants of HIV outcomes have been limited in their focus on small subgroups, and/or on a small number of social determinants. To date, we still lack the fundamental understanding of the impacts of social determinants on the past, present and the future outcomes of HIV/AIDS at the country level. To address this knowledge gap, we will estimate the impact of various social determinants on the course of the HIV/AIDS epidemic using a novel analytical process that seeks to reconcile the evidence and results from natural history models and formal demographic models. The proposed model will be able to quantify the impact of different social determinants on the epidemic, to examine how different social determinants have affected the course of the epidemic and estimate their relative importance at the population level. We will leverage vast data on socio- economic covariates and behavioral risk factors from the Global Burden of Disease Study, national surveys and other sources to quantify the impact of social determinants on incidence, prevalence, and mortality of HIV/AIDS for 188 countries from 1970 to 2015. We will develop a novel analytical framework that is able to incorporate these social determinants and is based on current models that estimate the course of the HIV/AIDS epidemic to quantify the relative contribution of different social determinants. This model will be the first of its kind to enable more accurate assessment of the impact of social determinants on the ultimate measurements of the epidemic: incidence, prevalence and mortality of HIV/AIDS. Results from this analysis can help guide targeted investment and intervention to further reduce the burden of HIV/AIDS at the country level.