Institute of Human Genetics, University Hospital-Friedrich Schiller University Jena, Kollegiengasse 10, Jena, Germany.
Eur J Clin Nutr. 2011 Feb;65(2):151-9. doi: 10.1038/ejcn.2010.245. Epub 2010 Nov 3.
BACKGROUND/OBJECTIVES: To evaluate the screening performance of body mass index (BMI) and waist circumference (WC) for excess adiposity. In addition, the diagnostic accuracy of cutoffs from different international and national reference systems based on BMI and WC was investigated.
SUBJECTS/METHODS: Data from 2132 Jena children aged 7-14 years conducted in 2005/2006 were analyzed. Receiver operating characteristic (ROC) curves were constructed to assess BMI and WC, as screening measures for excess adiposity (derived from skinfolds). Sensitivity, specificity and positive predictive values (PPVs) were calculated for two BMI-based classification systems (IOTF and German reference) and sample-based WC cutoffs.
The BMI as well as the WC performed well in detecting excess fat mass, indicated by areas under the ROC curve (AUC) close to 1.0, with slightly greater AUCs for BMI than for WC in both sexes. The specificity of all reference systems was high for both sexes (95 to 98%). However, their sensitivities were low (53-67% in boys; 51-67% in girls). PPV were higher for the German reference and the sample-based WC cutoffs than for the IOTF reference, and higher in girls than in boys.
The setting in which the reference system should be used is important for the selection of the reference system. The results support the use of the BMI-based references for monitoring in epidemiological studies. The sample-based cutoffs for WC should be refined for clinical use on national level.
背景/目的：评估身体质量指数（BMI）和腰围（WC）对肥胖的筛查性能。此外，还研究了基于 BMI 和 WC 的不同国际和国家参考系统的截断值的诊断准确性。
受试者/方法：分析了 2005/2006 年在耶拿进行的 2132 名 7-14 岁儿童的数据。构建了受试者工作特征（ROC）曲线，以评估 BMI 和 WC 作为肥胖的筛查指标（来自皮褶厚度）。计算了两种基于 BMI 的分类系统（IOTF 和德国参考）和基于样本的 WC 截断值的敏感性、特异性和阳性预测值（PPV）。
BMI 和 WC 在检测体脂过多方面表现良好，ROC 曲线下面积（AUC）接近 1.0，表明两者在男性和女性中的 AUC 均略大于 WC。所有参考系统的特异性均较高（男性为 95%至 98%；女性为 95%至 98%）。然而，它们的敏感性较低（男性为 53%至 67%；女性为 51%至 67%）。德国参考和基于样本的 WC 截断值的 PPV 高于 IOTF 参考，女性的 PPV 高于男性。
参考系统的使用环境对于参考系统的选择很重要。结果支持在流行病学研究中使用基于 BMI 的参考。基于样本的 WC 截断值需要在国家层面上进一步细化，以用于临床。
