在连续结果的楼梯设计中推断处理效应:一个模拟研究
Ehsan Rezaei-Darzi1, Kelsey L Grantham1, Andrew B Forbes1
1School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia.
BMC medical research methodology
|May 10, 2025
概括
楼梯设计需要谨慎使用,特别是只有少数集群. 正确指定相关性结构对于在临床试验中准确推断治疗效果至关重要.
科学领域:
- 临床试验设计 临床试验设计
- 统计学方法论 统计学方法论
- 医疗保健服务研究 医疗服务研究
背景情况:
- 楼梯设计是一种不完整的阶梯形设计.
- 它们与标准设计的不同之处在于,它们要求每个集群的数据周期较少.
- 现有的功率计算公式是基于非对称的结果.
研究的目的:
- 为了评估楼梯设计现有功率计算公式的有限样本性能.
- 评估错误指定相关性结构对治疗效应推断的影响.
- 在各种现实的试验环境下检查性能.
主要方法:
- 基本楼梯设计的模拟研究,具有连续的结果.
- 在可交换和区块可交换的集群内相关结构下分析数据.
- 使用带有小样本校正的线性混合模型 (Kenward-Roger,Satterthwaite).
主要成果:
- 具有可交换结构的萨特斯威特校正可以控制具有足够集群的I型错误.
- 错误指定相关性结构 (可交换与区块可交换) 可以膨胀I型错误并减少置信区间覆盖范围.
- 如果有足够的集群,推断是可靠的,但对于每个序列有一个集群的设计,建议谨慎.
结论:
- 每个序列只有一个集群的楼梯设计要求谨慎应用.
- 对于有效的治疗效果估计,建议采用与衰变相关的相关性结构.
- 对相关性结构的准确建模对于可靠的统计推理至关重要.
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