Covariate imbalance and random allocation in clinical trials

作者：Stephen John Senn · 发表于：Statistics in Medicine · 年份：1989 · DOI：10.1002/sim.4780080410 · 被引用次数：286 · 研究领域：Statistical Methods in Clinical Trials、Statistical Methods and Bayesian Inference、Statistical Methods and Inference

A model is developed to estimate the effect of covariate imbalance on the size of a test of treatment efficacy in randomized clinical trials comparing two treatments when dispersion parameters are known. It is concluded that tests of homogeneity on the covariates should not be performed, that covariate imbalance is just as much a problem for large studies as for small ones in terms of effect on size, and that the effect of correlation between covariates and measures of efficacy is more complex than has previously been suggested. The best way to adjust for covariate imbalance is by an analysis of covariance.