在受限随机化设计中对个别分配的分配可预测性,用于双臂均等分配试验
Wenle Zhao1, Sherry Livingston1
1Medical University of South Carolina, Charleston, South Carolina, USA.
Statistics in medicine
|January 24, 2025
概括
临床试验中的分配可预测性在个别分配和序列平均值之间有所不同. 序列平均值可能低估了选择偏差风险,特别是在较短的试验中.
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
- 随机化技术 随机化技术
背景情况:
- 限制随机化对于尽量减少临床试验中的选择偏差至关重要.
- 了解分配可预测性是评估随机化程序完整性的关键.
- 评估可预测性的现有方法可能无法完全捕捉所有设计中的风险.
研究的目的:
- 为了推导和分析个别治疗分配和序列平均值的分配可预测性.
- 用特定标准评估受限随机化设计中的可预测性.
- 为了比较单个任务的可预测性与序列平均值.
主要方法:
- 使用治疗失衡过渡矩阵和条件分配概率.
- 开发了适用于双臂,同等分配试验的方法,最大不平衡限制.
- 分析了基于奇数/偶数序列顺序和收率的分配可预测性.
主要成果:
- 在双臂试验中的分配可预测性根据分配顺序 (奇数/偶数) 交替.
- 序列平均可预测性比个别赋值可预测性更慢地趋同.
- 使用序列平均值的比较对序列长度敏感,可能低估了偏差风险.
结论:
- 个人分配可预测性提供了比序列平均值更准确的风险评估,特别是在短期试验中.
- 序列长度显著影响平均可预测性指标的可靠性.
- 需要仔细考虑评估方法,以防止低估随机化中的选择偏差.
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