Covariate adjustment in subgroup analyses of randomized clinical trials: A propensity score approach

  title={Covariate adjustment in subgroup analyses of randomized clinical trials: A propensity score approach},
  author={Siyun Yang and Fan Li and Laine E Thomas and Fan Li},
  journal={Clinical Trials},
  pages={570 - 581}
Background: Subgroup analyses are frequently conducted in randomized clinical trials to assess evidence of heterogeneous treatment effect across patient subpopulations. Although randomization balances covariates within subgroups in expectation, chance imbalance may be amplified in small subgroups and adversely impact the precision of subgroup analyses. Covariate adjustment in overall analysis of randomized clinical trial is often conducted, via either analysis of covariance or propensity score… 

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