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在大纵向数据中识别生物学上不可信的值:一个应用到来自巴西食品和营养监测系统的儿童生长数据的例子
Juliana Freitas de Mello E Silva1, Natanael de Jesus Silva1,2, Thaís Rangel Bousquet Carrilho3,4
1Centre for Data and Knowledge Integration for Health, Gonçalo Moniz Institute, Oswaldo Cruz Foundation, Salvador, BA, Brazil.
BMC medical research methodology
|February 15, 2024
概括
删除人口异常值显著影响儿童成长数据分析,纵向异常值删除的影响较小. 这两者对于准确的轨迹评估至关重要.
科学领域:
- 儿童生长监测 儿童生长监测
- 生物统计学 生物统计学
- 公共卫生监督 公共卫生监督
背景情况:
- 对大型数据集来说,评估在纵向人体测量数据中识别生物学上不可信的值的策略至关重要.
- 本研究研究了儿童生长数据中的异常值去除技术.
研究的目的:
- 评估删除人口和纵向异常值对儿童成长轨迹和指标患病率的影响.
- 了解大型数据集中不同异常值检测截止值的有效性.
主要方法:
- 来自巴西食品和营养监督系统的0-59个月儿童的身高和体重数据的分析.
- 使用世卫组织增长图的z-score识别人口异常值.
- 纵向异常值使用线性混合效应模型的残余值进行标记,并测试了截止值 (-3/+3 到 -6/+6).
主要成果:
- 分析了近1100万儿童的5000多万份记录.
- 人口异常值影响了4.7-5.7%的长度/高度和4.7-5.2%的体重测量.
- 纵向异常值在0.01%至1.50%之间,取决于测量和性别.
- 删除人口异常值对增长轨迹的影响比删除纵向异常值更大.
结论:
- 人口和纵向异常值都在儿童生长数据中发现了不可思议的值.
- 删除人口异常值对于大型行政数据集中的总结统计数据更为关键.
- 准确评估增长轨迹需要识别和消除两种类型的异常值.
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