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Selecting a biased-coin design. (English) Zbl 1332.62264
Summary: Biased-coin designs are used in clinical trials to allocate treatments with some randomness while maintaining approximately equal allocation. More recent rules are compared with B. Efron [Biometrika 58, 403–417 (1971; Zbl 0226.62086)] biased-coin rule and extended to allow balance over covariates. The main properties are loss of information, due to imbalance, and selection bias. Theoretical results, mostly large sample, are assembled and assessed by small-sample simulations. The properties of the rules fall into three clear categories. A Bayesian rule is shown to have appealing properties; at the cost of slight imbalance, bias is virtually eliminated for large samples.

##### MSC:
 62K05 Optimal statistical designs 62P10 Applications of statistics to biology and medical sciences; meta analysis
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##### References:
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