Unbiased Analysis of Today's Healthcare Issues
Summarized from a nice review paper by Basu, Unuigbe and Masseria (2023). Stratifying by Quintiles of propensity scores (PS). Under this approach, the empirical distribution of the estimated PS across the entire sample (including treated and untreated participants) is divided into quintiles. Indicator variables for the first 4 quintiles are then used as covariates, along…
Difference-in-differences attempts to measure causal effects using changes in outcomes across different groups. One of the key assumptions of differences-in-differences specification are that pre-period trends are similar across these groups. But what happens if these pre-period trends do appear? Can the use of propensity score matching solve the problem. According to a paper by Daw…
What options are available for propensity score matching algorithms? Baser (2006) describes a number of popular options. Stratified Matching. In this method, the range of variation of the propensity score is divided into intervals such that within each interval, treated and control units have, on average, the same propensity score. Differences in outcome measures between…