Schreiner P J, Pitkäniemi J, Pekkanen J, Salomaa V V
Department of Epidemiology, University of Minnesota, Minneapolis, USA.
J Clin Epidemiol. 1995 Nov;48(11):1361-7. doi: 10.1016/0895-4356(95)00052-6.
We examined the repeatability of near-infrared interactance (NIR) body fat determination as compared with that of body mass index (BMI), waist-to-hip ratio (WHR), and waist girth. Thirty-nine volunteers (16 men, 23 women) had percent body fat (%BF) measurements made with a portable NIR device as well as the standard anthropometric indices of height, weight, waist girth, and hip circumference. Frame size and physical activity levels were also determined. For each participant, three independent measurements of each index were made by two trained readers during a 2-week period. The two readers varied significantly in their measurement of %BF and hip circumference. The variability in %BF was largely due to differences between the first and the second measurements, and only for one of the readers. Second and third measurements were not statistically significantly different for either reader, suggestive of a training effect. Variance component calculations revealed that the reliability of NIR is 95.3%, compared with 99.9% for BMI; 93.4% for waist girth; and 82.4% for WHR, with the majority of the remaining variance accounted for by the method itself. We conclude that the NIR method has good repeatability, with low intra- and interobserver variability, provided that readers are carefully trained. However, the NIR device offers little advantage in reliability over conventional measures of adiposity such as waist girth or BMI, and requires additional input of weight, height, frame size, physical activity level, age, and gender data to calculate %BF. Associations of NIR and other anthropometric indices with cardiovascular risk factors in this population will provide additional insight into the merit of NIR body fat assessment.
我们研究了近红外交互作用（NIR）测定体脂的可重复性，并与体重指数（BMI）、腰臀比（WHR）和腰围进行比较。39名志愿者（16名男性，23名女性）使用便携式NIR设备进行了体脂百分比（%BF）测量，并测量了身高、体重、腰围和臀围等标准人体测量指标。还确定了体型和身体活动水平。在两周内，由两名经过培训的人员对每位参与者的每个指标进行三次独立测量。两名测量人员在%BF和臀围测量结果上存在显著差异。%BF的变异性主要是由于第一位和第二位测量人员之间的差异，且仅针对其中一名测量人员。两位测量人员的第二次和第三次测量在统计学上均无显著差异，这表明存在训练效应。方差成分计算显示，NIR的可靠性为95.3%，而BMI为99.9%；腰围为93.4%；WHR为82.4%，其余大部分方差由测量方法本身造成。我们得出结论，NIR方法具有良好的可重复性，观察者内和观察者间变异性较低，前提是测量人员经过仔细培训。然而，与腰围或BMI等传统肥胖测量方法相比，NIR设备在可靠性方面优势不大，并且计算%BF需要额外输入体重、身高、体型、身体活动水平、年龄和性别数据。该人群中NIR与其他人体测量指标与心血管危险因素之间的关联将为NIR体脂评估的优点提供更多见解。
