PROPENSITY SCORE ANALYSIS AND ASSESSMENT OF PROPENSITY SCORE APPROACHES USING SAS ® PROCEDURES

Propensity score analysis is frequently used to reduce the potential bias in estimated effects obtained from observational studies. Appropriate implementation of propensity score adjustments is a multi-step process presenting many alternatives for researchers in terms of estimation and conditioning methods. Further, evaluation of the sample data after conditioning on the propensity score informs researchers about threats to the validity of the adjustments obtained from such an analysis. This paper describes the steps required for a propensity score analysis, and presents SAS code that can be used to implement each step.

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