There is debate regarding the optimal time to initiate antiretroviral therapy (ART) in resource-limited settings. The research goal of Dr. Serena Koenig, an infectious disease fellow and associate physician in the Division of Social Medicine and Health Inequalities at Brigham and Women's Hospital, is to determine the optimal time to initiate ART in patients with symptomatic HIV disease in Haiti using a decision modeling approach to incorporate complex trade-offs among clinical benefits, risk of toxicity, and financial cost. She will carry out the proposed health outcomes study in parallel with a randomized control trial that will be conducted by the GHESKIO research center in Port au Prince to compare survival and TB outcomes for early versus delayed treatment of patients with pre-AIDS symptomatic HIV disease. She will be mentored by Drs. Sue Goldie, Warren Johnson, and Jean William Pape. This research plan is composed of three specific aims: 1. To measure quality of life and adherence to ART among patients in the early and delayed treatment groups in the clinical trial, and to conduct an interview study of patients and other members of the Haitian community to compare the values they place on health at different stages of HIV disease. 2. To perform a cost analysis of HIV care in Haiti using clinical trial data and retrospective data collected on patients treated at GHESKIO and elsewhere in Haiti. This analysis will estimate the initial, induced, and averted costs of health-care resources over time for early versus delayed ART. 3. To conduct a cost-effectiveness analysis of early versus delayed ART in Haiti from a societal perspective. Outcome measures will include life expectancy, lifetime total direct medical costs, and costeffectiveness in dollars per quality-adjusted life-year gained and in disability-adjusted life-year gained. Results will be stratified based on the presence or absence of active tuberculosis (TB) infection and sensitivity analyses will examine the impact of adherence rates. ? ?