在英格兰,按年龄和性别分类的儿童加速度计测量体育活动的学校级集群内部相关系数和自相关系数
Ruth Salway1, Russell Jago2,3,4, Frank de Vocht2,3
1Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK. Ruth.Salway@bristol.ac.uk.
BMC medical research methodology
|August 9, 2024
概括
对儿童体育活动干预措施的精确样本大小计算需要可靠的集群内相关系数 (ICC) 估计. 这项研究为基于学校的试验提供了关键的ICC,集群自相关性 (CAC) 和个人自相关性 (IAC) 值.
科学领域:
- 流行病学 流行病学
- 生物统计学 生物统计学
- 儿童健康 儿童健康
背景情况:
- 基于学校的集群设计是评估儿童体育活动干预措施的常见方法.
- 准确的样本大小估计取决于集群内相关系数 (ICC) 值.
- 现有的ICC对加速度计测量身体活动的估计很少,并且根据年龄和结果而异.
研究的目的:
- 估计英格兰儿童加速度计测量身体活动的学校级ICC,集群自相关性 (CAC) 和个人自相关性 (IAC).
- 为未来基于学校的集群试验提供数据,以告知样本大小计算.
- 根据年龄组和性别分层估计.
主要方法:
- 从七个大型英语数据集 (2002-18年) 收集数据,其中包括超过13,500名学生和540所学校.
- 使用线性混合效应模型来估计中度至强度体力活动 (MVPA) 和久坐时间的ICC.
- 估计CAC和IAC使用来自1,252所学校和34,923名学生的综合纵向数据.
主要成果:
- 在小学 (0.07-0.08) 的周日MVPAICC比中学 (0.04-0.10) 高.
- 联合CAC为0.60 (95%CI:0.44-0.72) 和IAC为0.46 (95%CI:0.42-0.49),无论随访时间如何.
- 对于MVPA的估计比静坐时间更高,对于平日与整个星期的估计也更高.
结论:
- 提供的ICC,CAC和IAC估计可以为未来基于学校的体育活动评估的设计提供信息.
- 估计在各个年龄段和环境中都是一致的,这表明它适用于其他高收入国家.
- 使用与研究设计和人口相匹配的适当估计对于充足的研究来说至关重要.
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