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组顺序设计和样本大小重新估计的好处随机对照试验评估的预防呼吸机相关的肺炎:一个模拟研究,由真实世界的数据提供信息
Holly Jackson1, Julien Sauser2,3, C H van Werkhoven4
1Infection Control Program, Faculty of Medicine, Geneva University Hospitals, World Health Organization Collaborating Center, Geneva, Switzerland. holly.jackson@hug.ch.
BMC medical research methodology
|November 12, 2025
概括
组序列设计 (GSD) 和样本大小重新估计 (SSR) 改善了随机对照试验 (RCT) 预防呼吸机相关肺炎 (VAP). 与固定RCT相比,这些自适应设计可以将预期的样本大小降低9-12%.
科学领域:
- 临床试验方法论 临床试验方法论
- 传染病流行病学 传染病流行病学
- 临界护理医学 临界护理医学
背景情况:
- 呼吸机相关肺炎 (VAP) 是一种与医疗相关的重要感染,患病率和死亡率高.
- 传统的随机对照试验 (RCT) 面临挑战,因为患者数量和事件率较低,特别是针对病原体的干预措施.
- 适应性试验设计,如组序列设计 (GSD) 和样本大小重新估计 (SSR),为提高RCT效率提供了潜在的解决方案.
研究的目的:
- 探索GSD和SSR在VAP预防的模拟优越性试验中提供的效率改进.
- 为了比较不同GSD和SSR参数对预期和最大样本大小的影响.
- 评估适应性设计在各种假设和真实的预防效应下的性能.
主要方法:
- 模拟基于前性观察性医院网络研究 - - 对抗肺炎策略随机评估的准备 (HONEST-PREPS) 的数据.
- 测试了各种GSD (Pocock,O'Brien Fleming边界) 和SSR设计,不同的停止边界,临时分析时间和假设的预防效应.
- 使用了时间到事件分析,危险比率代表了主要的终点.
主要成果:
- 为了达到30%的VAP降低 (危险比为0.68),一个标准的RCT需要1291名患者.
- 使用波考克边界的GSD产生了较小的预期样本大小 (1128),但比奥布莱恩弗莱明边界 (E[N]=1170,max(N) =1389) 更大的最大 (1578).
- 当初效应估计不正确时,SSR比GSD更有效地维持了所需功率,对预期样本大小的影响最小.
结论:
- GSD和SSR是VAP预防中优越性试验的有效适应性设计.
- 这些设计优于固定RCT,可将预期样本大小减少9-12%.
- 在VAP预防研究的试验设计阶段,应考虑适应性设计.
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