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调整开关多次处理:开关应该单独处理还是组合处理?

Helen Bell Gorrod¹, Shahrul Mt-Isa², Jingyi Xuan³

¹Sheffield Centre for Health and Related Research, School of Medicine and Population Health, University of Sheffield, Sheffield, South Yorkshire, UK.

Statistical methods in medical research

|January 17, 2025

概括

在随机对照试验 (RCT) 中调整多个治疗开关,使用反向概率审查权重 (IPCW) 或两阶段估计 (TSE) 显示了相似的偏差,无论开关是否组合或单独分析. 结合开关与RCT中治疗转换的单独分析一样有效.

科学领域:

生物统计学生物统计学
临床试验方法论临床试验方法论
流行病学流行病学

背景情况:

在随机对照试验 (RCT) 中,治疗转换是常见的.
现有的调整方法往往侧重于单一治疗开关.
处理多个处理开关需要强大的统计方法.

研究的目的:

评估统计方法调整治疗效果在多个治疗切换在RCT的存在.
为了比较两个调整策略的表现:"单独治疗"与"联合治疗".
在多个切换场景下,评估审查权重 (IPCW) 和两阶段估计 (TSE) 的逆概率的偏差和趋同.

主要方法:

模拟了48个场景,其中包括不同的切换比例,治疗效果,切换到治疗的数量和审查.
应用IPCW和TSE方法来调整治疗切换.
对比"单独处理" (为每个开关类型单独调整) 和"组合处理" (为所有开关一起调整).
使用受限平均存活时间和模型趋同频率的平均百分比偏差来评估性能.

主要成果:

无论是"单独治疗"还是"结合治疗"的方法,在IPCW和TSE应用中都产生了类似的偏差水平.
与将所有开关结合起来相比,单独分析每个开关类型没有发现显著的优势.
选择的方法在各种模拟参数中显示出合理的性能.

结论:

通过组合所有开关来调整多个处理开关,与在RCT中单独分析每个开关类型一样有效.
这些发现简化了临床试验中复杂的治疗转换模式的分析.
该研究为生物统计学家和临床试验设计人员提供了处理治疗转换的实用见解.

关键词:

处理切换的切换处理这是一个反事实性的反事实.卫生技术评估卫生技术评估多次治疗,多次治疗.瘤学在瘤学方面.总体存活率总体存活率生存分析,生存分析.时间依赖的混.时间到事件的结果.

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