Clinical Trials with an Adaptive Choice of Hypotheses

  • Gerhard Hommel
  • Siegfried Kropf


In a clinical trial with an adaptive interim analysis it is possible to modify not only the design, but even the hypothesis(es) of interest, in a formally correct manner. Two examples of clinical trials are described where modifications of hypotheses are based on substantial scientific reasons. Generally, it is emphasized that the danger of manipulation caused by flexible designs must be controlled by very restrictive guidelines.

Key Words

Adaptive design Group-sequential design Closure test Multiple endpoints; A priori ordered hypotheses 


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Copyright information

© Drug Information Association, Inc 2001

Authors and Affiliations

  • Gerhard Hommel
    • 1
  • Siegfried Kropf
    • 2
  1. 1.Institute for Medical Statistics and DocumentationUniversity of MainzMainzGermany
  2. 2.Biometrician, Coordination Centre for Clinical TrialsUniversity of LeipzigLeipzigGermany

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