A Unified Three-Stage Weighting Framework for Causal Inference and Mediation Analysis under Case-Control Sampling (opens in new tab)

Case-control studies are widely used in epidemiology and biomedical research because they provide substantial efficiency gains when outcomes are rare or prospective follow-up is impractical. However, retrospective outcome-dependent sampling distorts the population outcome distribution, creating fundamental challenges for causal inference. We propose a unified three-stage weighting (3S-weighting) framework for causal inference and causal mediatio...