在复制测量分析混合模型中,在不假定直角性的情况下进行小样本推断调整
Kazushi Maruo1, Ryota Ishii1, Yusuke Yamaguchi2
1Department of Biostatistics, Institute of Medicine, University of Tsukuba, Tsukuba, Japan.
Journal of biopharmaceutical statistics
|October 30, 2024
概括
重复测量 (MMRM) 分析的混合模型可以在临床试验中产生偏见的标准错误. 本研究介绍了两种调整方法,以提高小样本的性能,并推一种用于预期异种性质的非大样本大小.
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
- 纵向数据分析 纵向数据分析
背景情况:
- 重复测量混合模型 (MMRM) 是纵向随机临床试验的常用统计方法.
- 标准的MMRM软件通常假定固定效应和共差参数之间的正交,在非正常错误分布下或完全缺失随机数据时,这些参数可能不成立.
- 这种假设可能会导致偏见的标准误差,特别是在小样本中.
研究的目的:
- 解决MMRM分析中的治疗效应标准误差中小样本偏差的问题.
- 提出新的方法来提高MMRM标准错误估计的准确性.
- 为实现这些改进的推理方法提供可访问的软件.
主要方法:
- 开发两种小样本调整方法,用于增加MMRM中的标准误差.
- 通过模拟研究评估拟议的方法.
- 在R包中实施拟议的方法,以便在实践中使用.
主要成果:
- 一种拟议的小样本调整方法在减少标准错误低估偏差方面表现出卓越的性能.
- 模拟结果表明,即使在一般情况下,推的方法也提供了经验保守主义.
- 开发的R包使得这些改进的推理过程更容易实现.
结论:
- 建议采用小样本调整方法进行MMRM分析,当样本大小不大且预计会有跨组异性时.
- 准确的标准误差估计对于在纵向研究中可靠的治疗效果推断至关重要.
- 该研究提供了一种实际的解决方案,以改善MMRM在具有挑战性的场景中的统计学严谨性.
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