# The central role of the propensity score in observational studies for causal effects

@article{Rosenbaum1983TheCR, title={The central role of the propensity score in observational studies for causal effects}, author={Paul R. Rosenbaum and Donald B. Rubin}, journal={Biometrika}, year={1983}, volume={70}, pages={41-55} }

Abstract : The results of observational studies are often disputed because of nonrandom treatment assignment. For example, patients at greater risk may be overrepresented in some treatment group. This paper discusses the central role of propensity scores and balancing scores in the analysis of observational studies. The propensity score is the (estimated) conditional probability of assignment to a particular treatment given a vector of observed covariates. Both large and small sample theory…

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