Mixed Models for Repeated Measures Should Include Time-by-Covariate Interactions to Assure Power Gains and Robustness Against Dropout Bias Relative to Complete-Case ANCOVA.

  title={Mixed Models for Repeated Measures Should Include Time-by-Covariate Interactions to Assure Power Gains and Robustness Against Dropout Bias Relative to Complete-Case ANCOVA.},
  author={Alejandro Schuler},
  journal={Therapeutic innovation \& regulatory science},
  • A. Schuler
  • Published 14 August 2021
  • Medicine, Mathematics
  • Therapeutic innovation & regulatory science
In randomized trials with continuous-valued outcomes, the goal is often to estimate the difference in average outcomes between two treatment groups. However, the outcome in some trials is longitudinal, meaning that multiple measurements of the same outcome are taken over time for each subject. The target of inference in this case is often still the difference in averages at a given timepoint. One way to analyze these data is to ignore the measurements at intermediate timepoints and proceed with… 

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