Group Sequential Clinical Trial Designs for Normally Distributed Outcome Variables

TL;DR

This paper introduces new Stata commands for designing and comparing group sequential clinical trials with normally distributed outcomes, emphasizing early stopping rules and efficiency.

Contribution

It provides novel computational tools for designing and evaluating classical group sequential designs using Stata, facilitating better trial planning.

Findings

New Stata commands for stopping boundaries and group size calculations.

Graphical comparison of different group sequential designs.

Enhanced tools for ethical and efficient trial decision-making.

Abstract

In a group sequential clinical trial, accumulated data are analysed at numerous time-points in order to allow early decisions about a hypothesis of interest. These designs have historically been recommended for their ethical, administrative and economic benefits. In this work, we discuss a collection of new Stata commands for computing the stopping boundaries and required group size of various classical group sequential designs, assuming a normally distributed outcome variable. Following this, we demonstrate how the performance of several designs can be compared graphically.