Biostatistics Seminar Series - Tianchen Qian, PhD

Title:  Causal Inference for Time-Varying Treatments and Binary Outcomes, with Application to Mobile HealthAbstract:  Advances in wearables and digital technology now make it possible to deliver behavioral mobile health interventions to individuals in their everyday life. The micro-randomized trial (MRT) is increasingly used to provide data to inform the construction of these interventions. This work is motivated by multiple MRTs that have been conducted or are currently in the field in which the primary outcome is a longitudinal binary outcome. The first, often called the primary, analysis in these trials is a marginal analysis that seeks to answer whether the data indicates that a particular intervention component has an effect on the longitudinal binary outcome. We develop an estimator that can be used as the basis of a primary analysis under plausible assumptions. Simulation studies are conducted to compare the estimators. We illustrate the developed methods using data from the MRT, SARA. In SARA, the goal is to use mobile intervention to increase self report among young adults.