试验臂的结果差异差异在放弃后作为失踪的指标-不是随机偏差在随机对照试验中的随机控制试验
Audinga-Dea Hazewinkel1,2, Kate Tilling1,2, Kaitlin H Wade1,2
1Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK.
Biometrical journal. Biometrische Zeitschrift
|September 20, 2023
概括
随机对照试验 (RCT) 中缺少的数据可能会导致偏见. 我们提出了一种新方法,使用试验臂之间的差异差异来检测连续结果中不随机缺失的结果 (MNAR).
科学领域:
- 生物统计学 生物统计学
- 临床试验方法论 临床试验方法论
- 健康研究方法 健康研究方法
背景情况:
- 随机对照试验 (RCT) 容易受到缺失数据的偏差影响,特别是当结果缺失时,不是随机 (MNAR).
- 评估MNAR的现有方法缺乏统计学严谨性,依赖于中断率和共变量分布的间接比较.
- 区分随机缺失 (MAR) 和随机缺失 (MNAR) 之间的区别对于公正的治疗效果估计至关重要.
研究的目的:
- 引入一种新的统计工具,用于在具有连续结果的RCT中评估MNAR风险.
- 为在完整案例分析 (CCA) 和多重归算 (MI) 估计中检测潜在偏差提供一种方法.
- 为了区分MNAR脱落的影响与其他差异不平等来源,如异质治疗效应.
主要方法:
- 建议使用试验臂间观察到的方差差作为MNAR脱落的指标.
- 利用在MAR脱落和均质假设下随机化时,差异应该在臂间相同的原则.
- 使用纵向数据来隔离MNAR效应,通过比较同一患者队列内的基线和最终随访差异.
主要成果:
- 观察到的条件试验臂差异不均表明MNAR脱落和治疗效果估计的潜在偏差.
- 拟议的方法可以区分MNAR放弃与异构的治疗效应或异构的结果错误.
- 模拟和应用证明了差异差法对CCA和MI的实用性.
结论:
- 在试验臂之间观察到的差异差异可以作为RCT中MNAR脱落的有价值指标.
- 拟议的方法增强了对临床试验分析数据完整性和潜在偏差的评估.
- 这种方法为研究人员提供了一个更强大的工具,以评估RCT发现的可靠性,缺少结果数据.
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