We discuss the multivariate (2L-variate) correlation structure and the asymptotic distribution for the group-sequential weighted logrank statistics formulated when monitoring two correlated event-time outcomes in clinical trials. The asymptotic distribution and the variance–covariance for the 2L-variate weighted logrank statistic are derived as available in various group-sequential trial designs. These methods are used to determine a group-sequential testing procedure based on calendar times or information fractions. We apply the theoretical results to a group-sequential method for monitoring a clinical trial with early stopping for efficacy when the trial is designed to evaluate the joint effect on two correlated event-time outcomes. We illustrate the method with application to a clinical trial and describe how to calculate the required sample sizes and numbers of events.
CITATION STYLE
Sugimoto, T., Hamasaki, T., Evans, S. R., & Halabi, S. (2020). Group-sequential logrank methods for trial designs using bivariate non-competing event-time outcomes. Lifetime Data Analysis, 26(2), 266–291. https://doi.org/10.1007/s10985-019-09470-4
Mendeley helps you to discover research relevant for your work.