集群随机试验与预试验和后试验:三,两和一级分析的等价性,以及样本大小计算
1Department of Methodology and Statistics, Maastricht University.
Multivariate behavioral research
|August 17, 2023
概括
这项研究表明,四种统计分析方法对集群随机试验与前试验后试验数据等同. 这些发现简化了对此类研究设计的样本大小计算.
科学领域:
- 生物统计学 生物统计学
- 流行病学 流行病学
- 临床试验 临床试验
背景情况:
- 集群随机试验 (CRT) 在个人随机化不可行或有治疗污染风险时是必不可少的.
- CRT将整个组 (集群) 分配给干预,需要特定的分析方法.
- 在CRT中,具有定量结果的测试前后测试设计是常见的.
研究的目的:
- 为了证明四种不同的分析CRT数据的统计方法与测试前和测试后测量的分析等价性.
- 用现实世界的CRT例子来比较这些方法.
- 根据已确定的等价值得出一个简化的样本大小计算方法.
主要方法:
- 对比一个三级混合效应模型 (集群,人,时间) 与非结构化的协变矩阵.
- 评估一个双层混合效应模型 (集群,人) 使用与基线的变化.
- 分析一个双层混合效应模型 (集群,时间) 与集群的平均值.
- 对从基线变化的集群平均值的一级分析的评估.
- 约束混合模型和预测共变量方法之间的等价证明.
主要成果:
- 对于集群随机试验与前试验后试验数据的四种不同的分析方法被发现是统计学上同等的.
- 该研究使用儿童心理健康CRT来说明这些等价值.
- 开发了一种简单的方法来计算基线测量CRT的样本大小.
结论:
- 这些分析方法的等价性为分析集群随机试验数据提供了灵活性.
- 简化样本大小计算方法有助于更有效的研究规划.
- 这些发现有助于集群随机试验研究的稳健统计实践.
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