一个在线样本大小计算器用于设计部分集群试验
Kylie M Lange1,2, Thomas R Sullivan1,2, Jessica Kasza3
1School of Public Health, The University of Adelaide, Adelaide, SA, Australia.
Clinical trials (London, England)
|January 31, 2026
概括
准确计算部分集群试验的样本大小对于适当的功率至关重要. 一个新的在线计算器可以帮助研究人员确定样本大小,并考虑试验设计中的复杂集群效应.
科学领域:
- 生物统计学 生物统计学
- 临床试验设计 临床试验设计
背景情况:
- 部分集群试验包括独立和集群观察,这在新生儿研究中很常见 (例如双胞胎).
- 准确的样本大小确定对于避免在这些试验中低或过度强大的治疗比较至关重要.
- 在部分集群试验中计算样本大小的现有工具是有限的,特别是 >2个集群大小的试验.
研究的目的:
- 引入一种新的在线应用程序,用于计算部分集群试验中的目标样本大小.
- 解决广泛的部分集群试验场景,包括那些最大集群大小大于2.
主要方法:
- 利用最近获得的设计效应,用于使用前随机化集群进行双臂部分集群试验.
- 考虑集群观测 (嵌套和交叉设计) 的集群和个人随机化.
- 包含关键参数:效果大小,显著程度,功率,集群大小范围,集群内相关性,随机化方法和分析模型.
主要成果:
- 开发了一个免费访问的R Shiny网络应用程序,实现了样本大小计算方法.
- 该计算器为设计部分集群试验提供了逐步指导.
- 考虑部分聚类的样本大小计算可能与忽视聚类的样本大小计算有很大差异.
结论:
- 部分聚类对临床试验功率和样本大小要求产生重大影响.
- 本文所介绍的计算器使研究人员能够准确地计算双臂试验中的部分聚类.
- 确保在部分集群研究设计中为连续和二进制结果提供适当的试验功率.
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