Effect Modification and Mediation | Understanding Medical Research

Effect mediation and effect modification sound alike and behave very differently. This video covers why adjusting for a mediator erases a real causal effect, how effect modification differs from a difference in baseline risk, and the rule to adjust for confounders but never for anything on the causal pathway. Chapters: 00:00 Introduction 01:08 The beef jerky experiment 01:53 Salt as a mediator 04:20 Never adjust for the causal pathway 05:55 Pregabalin, pain, and sleep 07:27 Mediation versus modification 10:22 What effect modification looks like 11:34 Topiramate and gene variants 12:58 Take-home points Learning objectives: After watching, you'll be able to: - Distinguish a mediator on the causal pathway from a confounder - Explain why adjusting for a mediator removes a real causal effect - Recognize effect modification and tell it apart from a difference in baseline risk 📺 Watch the full playlist on YouTube: https://www.youtube.com/playlist?list=PLh9mgdi4rNewVyTec_MVGxIbNSEeMhEsZ 🎓 Enroll on Coursera for assessments and a certificate: https://www.coursera.org/learn/medical-research 🌐 Explore more learning opportunities on Yale Online: https://online.yale.edu/courses/understanding-medical-research-your-facebook-friend-wrong