McAdams Mara A, Van Dam Rob M, Hu Frank B
Department of Epidemiology, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115, USA.
Obesity (Silver Spring). 2007 Jan;15(1):188-96. doi: 10.1038/oby.2007.504.
The purpose of this study is to evaluate the validity of BMI based on self-reported data by comparison with technician-measured BMI and biomarkers of adiposity.
We analyzed data from 10,639 National Health and Nutrition Education Study III participants > or =20 years of age to compare BMI calculated from self-reported weight and height with BMI from technician-measured values and body fatness estimated from bioelectrical impedance analysis in relation to systolic blood pressure, fasting blood levels of glucose, high-density lipoprotein-cholesterol, triglycerides, C-reactive protein, and leptin.
BMI based on self-reported data (25.07 kg/m2) was lower than BMI based on technician measurements (25.52 kg/m2) because of underreporting weight (-0.56 kg; 95% confidence interval, -0.71, -0.41) and overreporting height (0.76 cm; 95% confidence interval, 0.64, 0.88). However, the correlations between self-reported and measured BMI values were very high (0.95 for whites, 0.93 for blacks, and 0.90 for Mexican Americans). In terms of biomarkers, self-reported and measured BMI values were equally correlated with fasting blood glucose (r = 0.43), high-density lipoprotein-cholesterol (r = -0.53), and systolic blood pressure (r = 0.54). Similar correlations were observed for both measures of BMI with plasma concentrations of triglycerides and leptin. These correlations did not differ appreciably by age, sex, ethnicity, or obesity status. Correlations for percentage body fat estimated through bioelectrical impedance analysis with these biomarkers were similar to those for BMI.
The accuracy of self-reported BMI is sufficient for epidemiological studies using disease biomarkers, although inappropriate for precise measures of obesity prevalence.
本研究旨在通过与技术人员测量的体重指数（BMI）及肥胖生物标志物进行比较，评估基于自我报告数据得出的BMI的有效性。
我们分析了来自10639名年龄大于或等于20岁的国家健康与营养教育研究III参与者的数据，以比较根据自我报告的体重和身高计算出的BMI与技术人员测量值得出的BMI，以及通过生物电阻抗分析估计的体脂与收缩压、空腹血糖水平、高密度脂蛋白胆固醇、甘油三酯、C反应蛋白和瘦素之间的关系。
由于体重报告偏低（-0.56千克；95%置信区间为-0.71至-0.41）和身高报告偏高（0.76厘米；95%置信区间为0.64至0.88），基于自我报告数据的BMI（25.07千克/平方米）低于基于技术人员测量的BMI（25.52千克/平方米）。然而，自我报告的BMI值与测量的BMI值之间的相关性非常高（白人中为0.95，黑人中为0.93，墨西哥裔美国人中为0.90）。就生物标志物而言，自我报告的和测量的BMI值与空腹血糖（r = 0.43）、高密度脂蛋白胆固醇（r = -0.53）和收缩压（r = 0.54）的相关性相同。两种BMI测量方法与甘油三酯和瘦素的血浆浓度之间也观察到类似的相关性。这些相关性在年龄、性别、种族或肥胖状况方面没有明显差异。通过生物电阻抗分析估计的体脂百分比与这些生物标志物的相关性与BMI的相关性相似。
尽管基于自我报告的BMI不适用于精确测量肥胖患病率，但对于使用疾病生物标志物的流行病学研究而言，其准确性是足够的。
