Math & Stats Colloquium Series - Sept. 25, 2026 (Dr. Augustine Wigle)

Speaker:  Dr. Augustine Wigle

Affiliation: Wilfred Laurier University

Title: Doubly-robust estimation of individualized treatment rules in the presence of missing outcomes using network meta-analysis

Abstract: An optimal individualized treatment rule (ITR) is a function that takes a patient's characteristics, such as demographics, biomarkers, and treatment history, and outputs a treatment that is expected to give the best outcome. Single studies often have low power when it comes to estimating ITRs, and rarely compare all treatments of interest simultaneously. Network meta-analysis (NMA) is a method of synthesizing data from multiple studies to estimate the relative effects of a set of treatments. Recently, ITR NMA methods have been developed as an approach to pool data from multiple studies to enable simultaneous comparison of more treatments. Existing approaches are vulnerable to model misspecification and fail to address missing outcomes, which commonly occur in real data. We propose a doubly-robust method for estimating study-level ITRs that accommodates missing-at-random outcome data using the Bayesian bootstrap, and propose an improvement to the NMA model that incorporates the full variance-covariance matrix of study-specific estimates. In a simulation study, we show that our Bayesian ITR NMA method is more robust and efficient than the existing approach. We apply our method to the motivating dataset consisting of three studies of pharmacological treatments for MDD, and explore how ITR NMA results can support personalized decision making in this context.

Bio: Dr. Augustine Wigle is an Assistant Professor in the Department of Mathematics at Wilfrid Laurier University. Her research develops innovative statistical approaches for evidence synthesis and decision-making, with a particular focus on Bayesian methodology. Prior to joining Laurier, she earned her HBSc in Mathematical Sciences at the University of Guelph, her MMath and PhD in Statistics from the University of Waterloo, and held an NSERC Postdoctoral Fellowship at McGill University. Her work was recently recognized with the ASA Outstanding Statistical Application award.