UC Berkeley School of Public Health, 2115 Milvia Street, Third Floor, Berkeley, CA, 94704.
University of California at Berkeley, School of Public Health, 50 University Hall, Berkeley, CA 94720.
J Sch Health. 2019 Aug;89(8):629-635. doi: 10.1111/josh.12788. Epub 2019 May 28.
The accuracy of students' heights and weights measured by school staff for body mass index (BMI) screening/reporting has not been established. This study examined school staffs' measurement accuracy, comparing accuracy by staff- and student-level characteristics.
School staff and researchers measured the height and weight of 1008 4th-8th grade students, within 1 month of each other. Bland-Altman plots, mean differences, and intraclass correlation coefficients (ICCs) were calculated to examine measurement accuracy. Linear mixed effects models assessed accuracy by staff- and student-level characteristics.
Bland-Altman plots revealed no appreciable bias in differences between researcher and staff measurements. The mean absolute difference between researcher and school staff measurements were 1.0 ± 1.6 cm (height), 0.7 ± 1.8 kg (weight), and 0.4 ± 0.8 kg/m (BMI). Inter-rater ICC values were ≥0.97, demonstrating "excellent" reliability. Categorical weight status was correctly classified for 94% of students (kappa 0.90), and for 96% with a BMI ≥95th% (kappa 0.94). Physical education (PE) teachers were slightly less accurate than school nurses in measuring height (0.4 cm less accurate; p = .045) and weight (0.4 kg; p = .015).
School staff conducted height/weight measurements on 4th-8th grade students with high accuracy. Resultant school-based BMI reports using similar protocols should validly reflect weight status for almost all students.
学校工作人员对学生身高和体重进行的测量，用于进行身体质量指数（BMI）筛查/报告的准确性尚未得到证实。本研究通过比较工作人员和学生的特征，检验了工作人员的测量准确性。
学校工作人员和研究人员在彼此相隔 1 个月的时间内，对 1008 名 4 至 8 年级的学生进行了身高和体重的测量。通过 Bland-Altman 图、均值差异和组内相关系数（ICC），来检验测量的准确性。线性混合效应模型评估了工作人员和学生特征的准确性。
Bland-Altman 图显示，研究人员和工作人员测量结果之间的差异没有明显的偏差。研究人员和学校工作人员测量值之间的平均绝对差异为 1.0±1.6 厘米（身高）、0.7±1.8 公斤（体重）和 0.4±0.8 公斤/米（BMI）。评估者间 ICC 值≥0.97，表明具有“极好”的可靠性。94%的学生的体重状况分类正确（kappa 值为 0.90），96%的 BMI≥95%的学生分类正确（kappa 值为 0.94）。与学校护士相比，体育（PE）教师在测量身高（低 0.4 厘米；p=0.045）和体重（低 0.4 公斤；p=0.015）方面的准确性略低。
学校工作人员对 4 至 8 年级学生进行身高/体重测量的准确性较高。使用类似方案的基于学校的 BMI 报告应能有效反映几乎所有学生的体重状况。
