Toward a Clearer Definition of Selection Bias When Estimating Causal Effects.

ABSTRACT: Selection bias remains a subject of controversy. Existing definitions of selection bias are ambiguous. To improve communication and the conduct of epidemiologic research focused on estimating causal effects, we propose to unify the various existing definitions of selection bias in the literature by considering any bias away from the true causal effect in the referent population (the population before the selection process), due to selecting the sample from the referent population, as selection bias. Given this unified definition, selection bias can be further categorized into two broad types: type 1 selection bias owing to restricting to one or more level(s) of a collider (or a descendant of a collider) and type 2 selection bias owing to restricting to one or more level(s) of an effect mea

SUBMITTER: Lu H 

PROVIDER: S-EPMC9378569 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature