在疟疾集群随机试验中对集群间异质性的描述,以告知未来的样本大小计算
Joseph Biggs1, Joseph D Challenger2, Dominic Dee2
1International Statistics and Epidemiology Group, Department of Infectious Disease Epidemiology and International Health, London School of Hygiene and Tropical Medicine (LSHTM), London, UK. joseph.biggs1@lshtm.ac.uk.
Nature communications
|July 18, 2025
概括
针对疟疾干预的集群随机试验 (CRT) 需要因集群异质性而增加样本大小. 这项研究发现,实际的异质性 (k) 往往超过估计值,降低了研究能力,增加了无效结果的可能性.
科学领域:
- 流行病学 流行病学
- 生物统计学 生物统计学
- 全球健康 全球健康
背景情况:
- 集群随机试验 (CRT) 对于评估全社区疟疾干预措施至关重要.
- 在CRT中准确的样本大小计算需要考虑集群异质性,通常使用变化系数 (k).
- 低估k可以导致研究功率降低和假负结果的可能性增加.
研究的目的:
- 从现有的疟疾CRT中计算真实流行率和发病率k值.
- 调查实证k值对原始试验功率的影响.
- 确定与疟疾CRT中k值升高相关的因素.
主要方法:
- 从24个疟疾CRT收集的集群总结数据的元分析.
- 使用时刻方法和回归建模计算k值.
- 随机效应回归建模,以评估k对试验功率的影响,并探索相关因素.
主要成果:
- 对k的经验估计经常超过了原始样本大小计算中使用的估计.
- 较高的k值与发病结果,较低的疟疾流行环境和不均的干预覆盖率有关.
- 估计和经验k值之间的差异降低了研究功率和效果大小精度.
结论:
- 对k的知情估计对于稳健的疟疾CRT样本大小计算至关重要.
- 使用基于预期的流行或发病率的经验k估计,可以改善未来的研究设计.
- 解决与高k相关的因素可以提高疟疾干预评估的可靠性.
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