A0581
Title: Causal mediation analysis of non-mortality outcomes with follow up truncated by death
Authors: An-Shun Tai - National Tsing Hua University (Taiwan) [presenting]
Abstract: In the context of mediation analysis, the presence of death-truncated variables poses a challenge as conventional measures fail to accurately assess the role of a mediator in the effect of a treatment on a primary non-mortality outcome. The purpose is to introduce novel estimands survivor natural direct and indirect effects to address this issue. Exchangeability assumptions are employed to mitigate confounding effects, and empirical expressions are derived using information from a pretreatment surrogate variable akin to an instrumental variable. Three estimation approaches, model parameterization, generalized method of moments, and data-adaptive G-computation, are developed and applied using data from a National Emphysema Treatment Trial to illustrate the proposed method.
