COMPARISON OF ALTERNATIVE STRATEGIES FOR ANALYSIS OF LONGITUDINAL TRIALS WITH DROPOUTS

Abstract

The LOCF and DAO approaches cannot be recommended as strategies for handling missing responses, at least for these scenarios, because they provide biased estimates of treatment effects and biased tests of the null hypothesis of no treatment effect. Application of the various approaches to the analysis of clinical data from a longitudinal trial confirms the underestimation of the variability when the LOCF approach is used.