Discussiones Mathematicae Probability and Statistics 24(1) (2004) 85-108

ADAPTIVE BIASED-COIN DESIGNS FOR CLINICAL TRIALS WITH SEVERAL TREATMENTS

Anthony C. Atkinson

Department of Statistics
London School of Economics, London WC2A 2AE, UK

Abstract

Adaptive designs are used in phase III clinical trials for skewing the allocation pattern towards the better treatments. We use optimum design theory to provide a skewed biased-coin procedure for sequential designs with continuous responses. The skewed designs are used to provide adaptive designs, the performance of which is studied numerically for designs with three treatments. Important properties are loss and the proportion of allocation to inferior treatments. Regularisation to provide consistent parameter estimates greatly improves both these properties.

Keywords: c-optimal design; limiting allocation proportion; minimization; randomization; regularisation.

2000 Mathematics Subject Classification: 62K05, 62P10.

References

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Received 12 October 2003