Randomization is a common technique used in clinical trials to eliminate potential bias and confounders in a patient population. Equal allocation to treatment groups is the standard due to its optimal efficiency in many cases. However, in certain scenarios, unequal allocation can improve efficiency. In superiority trials with more than two groups, the optimal randomization is not always a balanced randomization. In noninferiority (NI) trials, additive margin with equal variance is the http://www.statlab.wisc.edu/shiny/SSNI/.

中文翻译：

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临床试验中随机化不平衡。

随机化是临床试验中用于消除患者群体中潜在偏倚和混杂因素的常用技术。由于在许多情况下其最佳效率，因此平均分配给治疗组是标准。但是，在某些情况下，分配不均可以提高效率。在两组以上的优越性试验中，最佳随机化并不总是平衡随机化。在非劣效性（NI）试验中，具有相等方差的加性余量为http://www.statlab.wisc.edu/shiny/SSNI/。