随机对照试验中的共变量调整:一般概念和实际考虑
Kelly Van Lancker1, Frank Bretz2,3, Oliver Dukes1
1Department of Applied Mathematics, Computer Science and Statistics, Ghent University, Ghent, Belgium.
Clinical trials (London, England)
|June 3, 2024
概括
随机对照试验中的共变量调整通过区分条件和边际治疗效应来提高准确性. 建议进行标准化,以便对边际效应进行可靠和高效的估计.
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
- 流行病学 流行病学
背景情况:
- 对随机对照试验 (RCT) 的共变量调整越来越感兴趣.
- 美国食品和药物管理局的指导强调了条件和边际治疗效应.
- 在临床实践中经常被忽视的效应之间的区别.
研究的目的:
- 审查RCT中的共变量调整以提高精度.
- 澄清条件估计和边际估计之间的差异.
- 将统计方法与所选择的估计值结合起来.
主要方法:
- 描述条件和边际估计.
- 突出边际效应常见方法中的错位.
- 倡导标准化方法的倡导者.
主要成果:
- 共变量调整可以提高RCT的精度.
- 标准化利用基线共变量提高效率.
- 标准化是强大的模型错误规范.
结论:
- 将分析与估计结果对齐至关重要.
- 标准化为边际效应估计提供了一种高效,强大的方法.
- 在RCT中对共变量进行调整的实际考虑.
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