2020 年 2 巻 2 号 p. 33-37
Propensity score is defined as the probability of each individual being assigned to the treatment group. Propensity score analysis has recently become the sine qua non of comparative effectiveness studies using retrospective observational data. The present report provides useful information on how to use propensity score analysis as a tool for estimating treatment effects with observational data, including (i) assumptions for propensity score analysis, (ii) how to estimate propensity scores and evaluate propensity score distribution, and (iii) four methods of using propensity scores to control covariates: matching, adjustment, stratification, and inverse probability of treatment weighting.