Estimating the Effect of Community-Based Interventions: the SEARCH trial and HIV prevention in East Africa

01 Dec
Friday, 12/01/2017 12:30pm to 2:00pm
Computer Science Building, Room 150/151
CSSI Lunch
Speaker: Laura Balzer

"Estimating the Effect of Community-Based Interventions: the SEARCH trial and HIV prevention in East Africa"

Abstract:  Cluster (group) randomized trials are increasingly implemented to learn about large-scale implementation as well as the direct, indirect, and population-level effects of interventions with proven individual-level efficacy. The SEARCH study, for example, is a large community randomized trial to evaluate the impact of early HIV diagnosis with immediate and streamlined treatment in rural Uganda and Kenya (NCT01864603). Evaluation of cluster-based interventions (randomized or not) presents significant methodological challenges. In particular, individual-level outcomes are correlated due to shared cluster-level factors, including the exposure, as well as social and biological interactions between individuals. In this talk, we describe 3 choices to optimize the design and analysis of the SEARCH study: pair-matching over complete randomization, specifying the causal parameter as sample effect instead of a population average parameter, and data-adaptive adjustment with targeted maximum likelihood estimation (TMLE). We conclude with practical implications and some ongoing challenges.

Bio:  Laura Balzer is an Assistant Professor of Biostatistics at UMass Amherst. She is a methodologist with substantive interests in global health, community-based participatory research, and social determinants of health. Her particular areas of expertise are Causal Inference and Machine Learning. Laura is the primary statistician for two cluster randomized trials: the SEARCH study for HIV prevention in East Africa and the SPIRIT study for TB prevention in Uganda. Overall, her work is informed by cross-disciplinary real-world problems and aims to ensure methodological advances in Academia translate into real-world impact.

Lunch will be provided, beginning at 12:15 pm
Talk begins at 12:30 pm