Please join us for the RCMAR CHIME Methodological Seminar on Monday, December 19 at 3:15 pm PDT.
Featuring: Roch Nianogo, MD, PhD, Assistant Professor, Department of Epidemiology, UCLA Fielding School of Public Health
Understanding and quantifying mechanisms and pathways through which a given exposure affects and an outcome is increasingly recognized as crucial for gaining better etiologic insights and identifying alternative intervention targets. Often times, it can be difficult, unethical or impractical for an intervention to target a given exposure (e.g. place of residence) for the purposes of reducing the incidence of a disease (e.g. asthma attacks). Instead, it might be more feasible or cost-effective to target a more downstream factor –we call mediator (e.g. industrial air pollution) that is on the causal pathway between the exposure and the outcome of interest. Methods to quantify these causal pathways are generally referred to as mediation analysis. While a number of such methods—conventional mediation analysis which originated in the social sciences have helped us understand how to decompose effects, many of them are limited for instance, when there exist some interactions between exposure and mediator. A more recent set of approaches, termed causal mediation analysis (CMA) based on the potential outcomes framework can readily deal with complexities including settings in which there exist interactions between exposure and mediator, when there are multiple mediators or when there exist time-varying confounding factors.
In this talk, we will present some introductory notions on how CMA works and outline a step by step procedure on how to implement a CMA for quantifying mechanisms and pathways through which a given exposure affects an outcome.
Speaker Bio: Roch Nianogo is an Assistant Professor in the Department of Epidemiology at the Fielding School of Public Health at the University of California, Los Angeles (UCLA) and former RCMAR/CHIME scholar. Dr. Nianogo’s work has involved the application of innovative and rigorous epidemiologic and causal inference methods for investigating the impact of lifestyle, metabolic and social interventions in preventing chronic diseases such as obesity, diabetes, Alzheimer’s disease and other dementias and translating such evidence into effective clinical, public health and policy interventions. In recent work, Dr. Nianogo has collaborated on research projects aiming to investigate the importance of modifiable risk factors for Alzheimer’s diseases and other dementias.