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在随机二期试验中分配不平等

R Jackson¹, T Cox¹

¹Department of Health Data Science, Block F, Waterhouse Building, University of Liverpool, L69 3GL.

Contemporary clinical trials

|August 7, 2025

概括

在II期临床试验中患者分配不平等,可以减少与平等分配相比的样本大小要求. 这种优化在响应率在治疗组之间显著不同时特别有效.

科学领域:

临床试验方法论临床试验方法论
生物统计学生物统计学
药学研究药学研究

背景情况:

在随机临床试验中,平等的患者分配是标准的,假定可以优化资源使用.
第二阶段研究设计经常使用二元终点和几率比率来评估疗效.
平等分配只在响应率相似时才能为几率比率提供最佳精度,这是临床兴趣有限的情景.

研究的目的:

为了获得临床试验的最佳分配比例,以最大限度地提高几率比率的精度.
为了比较在II期研究中不平等分配与平等分配的样本大小要求.

主要方法:

开发了分配比例,以便在预期响应率差异时最大限度地提高赔率比率的精度.
进行了样本大小计算,比较不平等和平等的分配设计.
使用基于Jung和Sargent的精确方法进行样本大小计算.

主要成果:

不平等的分配导致所需的样本大小较小,相比于平等的分配,保持相同的I型错误率和功率.
随着对照组的响应率接近0或1,随着固定相对治疗效应,样本大小的节约增加.
这表明在特定条件下通过不平等的分配获得了显著的效率增长.

结论:

设计II期研究的临床试验人员应考虑不平等的患者分配.
不平等的分配提供了大幅节省样本大小的潜力.
采用不平等的分配可以导致在临床试验中更有效地利用资源.

关键词:

第二阶段第二阶段随机排序随机排序随机排序样本的大小样本大小不平等的分配不平等的分配

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