On Testing Hypotheses in Response-Adaptive Designs Targeting the Best Treatment

  • Nancy Flournoy
  • Caterina May
  • Jose A. Moler
  • Fernando Plo
Conference paper
Part of the Contributions to Statistics book series (CONTRIB.STAT.)


We considerer a sequential, response-adaptive design for clinical trials which is characterized by the fact that it assigns patients to the best treatment with a probability converging to one. This property is optimal from an ethical point of view; in this paper we analyze some inferential problems related to the design. In particular, we want to establish, by means of a test of hypothesis, which treatment is superior, in the sense that it has greater mean response. Together with the natural generalization of the classical t-statistic, we introduce a statistic based on the probability of assigning patients to a treatment conditional on past observations. Theoretical properties of the tests are studied, together with numerical evaluations of the power for dichotomous responses.


Success Probability Empirical Power Ethical Point Dichotomous Response Simulated Clinical Trial 


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Thanks to Piercesare Secchi and Anna Maria Paganoni for the ideas and discussions which have stimulated this work.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Nancy Flournoy
    • 1
  • Caterina May
    • 2
  • Jose A. Moler
    • 3
  • Fernando Plo
    • 4
  1. 1.University of MissouriColumbiaUSA
  2. 2.Università degli Studi del Piemonte OrientaleNovaraItaly
  3. 3.Universidad Publica de NavarraPamplonaSpain
  4. 4.Universidad de ZaragozaZaragozaSpain

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