部分嵌套设计和其他嵌套或交叉设计的样本大小,当调整为基线时,具有连续结果
Steven Teerenstra1, Jessica Kasza2, Ruslan Leontjevas3,4
1Department for Health Evidence, Section Biostatistics, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.
Statistics in medicine
|June 22, 2023
概括
在随机对照试验中对基线测量进行调整,可显著减少所需的样本大小. 这种优化对于高效的试验设计和分析至关重要,特别是与相关的后续数据.
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
- 医疗保健服务研究 医疗服务研究
背景情况:
- 随机对照试验 (RCT) 通常涉及基线和后续测量.
- 由于群体或治疗师效应,治疗可以诱导随访结果的相关性.
- 现有的文献重点是仅使用后续数据进行分析.
研究的目的:
- 为了比较带有和没有基线调整的RCT的样本大小要求.
- 开发样本大小公式,包括基线跟踪相关性.
- 探索部分嵌套设计的实际设计考虑因素.
主要方法:
- 对样本大小要求进行比较分析.
- 为各种设计 (嵌套,集群RCT) 推导样本大小公式.
- 调查影响样本大小减少的因素 (变异,相关性).
主要成果:
- 根据基线测量进行调整,可减少RCT所需的样本大小.
- 样本大小的减少取决于基线和随访差异及其相关性.
- 为部分/完全嵌套和集群随机试验提供了新的公式.
结论:
- 基线调整是优化RCT样本大小的有效策略.
- 衍生的公式有助于对复杂设计进行高效的试验规划.
- 讨论了部分嵌套试验的实际设计考虑因素.
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