Optimal planning of adaptive two?stage designs

Adaptive designs are playing an increasingly important role in the planning of clinical trials. While there exists various research on optimal determination a two-stage design, non-optimal versions still frequently applied research. In this article, we strive to motivate application adaptive and give guidance how determine them. It is demonstrated that optimizing trial design with respect particular objective criteria can have substantial benefit over conventional sample size recalculation rules. Furthermore, show many practical situations, group-sequential almost negligible performance loss compared designs. Finally, illustrate be tailored specific operational requirements by customizing underlying optimization problem.