Results 231 to 240 of about 69,041 (263)

Adaptive biased-coin designs for clinical trials with several treatments

Discussiones Mathematicae Probability and Statistics, 2023
Summary: 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.
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An optimal response adaptive biased coin design with k heteroscedastic treatments

Journal of Statistical Planning and Inference, 2011
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Gwise, Thomas E., Zhou, Jianhui, Hu, Feifang   +2 more
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Covariate-adjusted inference for doubly adaptive biased coin design

Statistical Methods in Medical Research
Randomized controlled trials (RCTs) are pivotal for evaluating the efficacy of medical treatments and interventions, serving as a cornerstone in clinical research. In addition to randomization, achieving balances among multiple targets, such as statistical validity, efficiency, and ethical considerations, is also a central issue in RCTs.
Fuyi Tu, Wei Ma
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Tests Conditional on Imbalance with Biased Coin Designs.

1986
Abstract : Distributional properties of the treatment assignment variables T sub 1, ..., T sub n under Efron's (1971) biased coin design are derived. These properties are conditional on the terminal imbalance of the treatment allocation. Recursive procedures are presented for obtaining the conditional moments of T sub 1, ..., T sub n.
Edsel Pena, Myles Hollander
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Sequential Monitoring of Conditional Randomization Tests: Generalized Biased Coin Designs

Sequential Analysis, 2008
Abstract For the generalized biased coin class of randomization procedures, Smythe (1988) proved asymptotic normality of the conditional linear rank test. Clinical trialists often undertake interim analysis to determine whether to stop the trial early for a substantial treatment effect.
Yanqiong Zhang, William F. Rosenberger
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On inferences from Wei's biased coin design for clinical trials

Biometrika, 1990
Wei (1988) analyzed data from a clinical trial in which an urn-sampling model was used to allocate patients to treatments. The trial resulted in 11 patients being allocated to the experimental treatment, all successes, and with one patient allocated to the control treatment, a failure.
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Balance and randomness in sequential clinical trials: the dominant biased coin design

Pharmaceutical Statistics, 2014
AbstractEfron's biased coin design (BCD) is a well‐known randomization technique that helps neutralize selection bias, while keeping the experiment fairly balanced for every sample size. Several extensions of this rule have been proposed, and their properties were analyzed from an asymptotic viewpoint and compared via simulations in a finite setup. The
BALDI ANTOGNINI, ALESSANDRO, ZAGORAIOU, MAROUSSA   +1 more
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A two-dimensional biased coin design for dual-agent dose-finding trials

Clinical Trials, 2015
Background: Given the limited efficacy observed with single agents, there is growing interest in Phase I clinical trial designs that allow for identification of the maximum tolerated combination of two agents. Purpose: Existing parametric designs may suffer from over- or under-parameterization.
Zhichao, Sun, Thomas M, Braun
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Which design is better? Ehrenfest urn versus biased coin

Advances in Applied Probability, 2000
Two features are desired in designing a sequential clinical trial: randomness and balance. The former makes the ground for valid statistical inferences and the latter strengthens efficiency in inference procedures. Unfortunately randomness and balance can be in conflict with one another, and clinicians may be caught between the need for both of them ...
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Dose Finding Using the Biased Coin Up‐and‐Down Design and Isotonic Regression

Biometrics, 2002
Summary.We are interested in finding a dose that has a prespecified toxicity rate in the target population. In this article, we investigate five estimators of the target dose to be used with the up‐and‐down biased coin design (BCD) Introduced By Durham and Flournoy (1994,Statistical Decision Theory and Related Topics).These estimators are derived using
Stylianou, Mario, Flournoy, Nancy
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