# A Structural Approach to Selection Bias

@article{Hernn2004ASA, title={A Structural Approach to Selection Bias}, author={Miguel A. Hern{\'a}n and Sonia Hern{\'a}ndez-D{\'i}az and James M. Robins}, journal={Epidemiology}, year={2004}, volume={15}, pages={615-625} }

The term “selection bias” encompasses various biases in epidemiology. We describe examples of selection bias in case-control studies (eg, inappropriate selection of controls) and cohort studies (eg, informative censoring). We argue that the causal structure underlying the bias in each example is essentially the same: conditioning on a common effect of 2 variables, one of which is either exposure or a cause of exposure and the other is either the outcome or a cause of the outcome. This structure… Expand

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