对比随时间推移的斜率的试验进行功率和样本大小计算:介绍斜率功率命令.
Stephen Nash1, Katy E Morgan2, Chris Frost2
1Department of Infectious Disease Epidemiology London School of Hygiene and Tropical Medicine London, UK.
概括
规划临床试验来减缓疾病进展是简单的新坡度功率命令. 该工具用于计算试验的样本大小和统计能力,分析随时间变化的结果,使用线性混合模型.
科学领域:
- 生物统计学 生物统计学
- 临床试验设计 临床试验设计
- 纵向数据分析 纵向数据分析
背景情况:
- 旨在减缓疾病进展的临床试验通常通过比较治疗组之间的随时间变化 (斜率) 来分析连续结果.
- 对这些试验进行准确的样本大小计算需要估计受试者之间和受试者内部的变异性,这些变异性通常是未知的.
- 对于斜率结果试验的样本大小计算的代数复杂性可能是有效试验规划的障碍.
研究的目的:
- 介绍slopepower,一个用户友好的命令,用于在试验中比较斜率结果的样本大小和功率计算.
- 提供基于线性混合模型方法的实用工具,用于规划具有纵向数据的临床试验.
- 为了证明斜率功率在确定各种试验设计所需的样本大小的实用性.
主要方法:
- 斜率功率命令使用线性混合模型方法,基于对纵向数据的既定统计方法.
- 它分为两个阶段运行:首先,使用线性混合模型从用户提供的数据中估计平均斜率,方差和共方差.
- 其次,它将这些估计与治疗有效性和未来试验设计的用户定义参数相结合,以计算样本大小或功率.
主要成果:
- 斜率功率命令为分析斜率结果的试验提供了对样本大小和功率计算的简化方法.
- 它简化了此类设计之前所需的复杂代数,使试验规划更容易获得.
- 该工具有助于在不同的潜在试验设计中比较所需的样本大小.
结论:
- 斜率功率指令是设计临床试验的研究人员的一个有价值的工具,可以评估随时间推移的疾病进展.
- 它提高了样本大小确定效率和准确性,这对于资源分配和研究有效性至关重要.
- 这个命令有助于优化试验设计,使不同规划场景的知情比较.
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