Department of Biometry, Bremen Institute for Prevention Research and Social Medicine, University of Bremen, Germany.
Int J Obes (Lond). 2011 Apr;35 Suppl 1:S79-87. doi: 10.1038/ijo.2011.38.
To describe the design, measurements and fieldwork of the IDEFICS (Identification and prevention of dietary- and lifestyle-induced health effects in children and infants) physical activity and body composition validation study, and to determine the potential and limitations of the data obtained.
Multicentre validation study.
A total of 98 children from four different European countries (age: 4-10 years).
An 8-day measurement protocol was carried out in all children using a collaborative protocol. Reference methods were the doubly labelled water method for physical activity, and a three- and a four-compartment model for body composition. Investigated field methods were accelerometers, a physical activity questionnaire and various anthropometric measurements.
For the validation of physical activity field methods, it was possible to gather data from 83 to 89 children, laying the basis for age- and sex-specific results. The validation of body composition field methods is possible in 64-80 children and allows sex-specific analyses but has only limited statistical power in the youngest age group (<6 years). The amount of activity energy expenditure (AEE) varied between centres, sexes and age groups, with boys and older children having higher estimates of AEE. After normalisation of AEE by body weight, most group-specific differences diminished, except for country-specific differences.
The IDEFICS validation study will allow age- and sex-specific investigation of questions pertaining to the validity of several field methods of body composition and physical activity, using established reference methods in four different European countries. From the participant analyses it can be concluded that the compliance for the investigated field methods was higher than that for the reference methods used in this validation study.
描述 IDEFICS（儿童和婴儿饮食和生活方式引起的健康影响的识别和预防）身体活动和身体成分验证研究的设计、测量和现场工作，并确定所获得数据的潜力和局限性。
多中心验证研究。
来自四个不同欧洲国家的共 98 名儿童（年龄：4-10 岁）。
所有儿童均采用协作方案进行为期 8 天的测量方案。参考方法是双标记水法测定身体活动，以及三腔和四腔模型测定身体成分。研究的现场方法是加速度计、体力活动问卷和各种人体测量。
对于身体活动现场方法的验证，可以从 83 到 89 名儿童中收集数据，为特定年龄和性别的结果奠定基础。身体成分现场方法的验证在 64-80 名儿童中是可行的，允许进行性别分析，但在最小年龄组（<6 岁）中统计能力有限。活动能量消耗（AEE）量因中心、性别和年龄组而异，男孩和年龄较大的儿童的 AEE 估计值较高。在通过体重归一化 AEE 后，除了特定国家的差异外，大多数特定于组的差异都减少了。
IDEFICS 验证研究将允许使用四个不同欧洲国家的既定参考方法，针对几种身体成分和身体活动的现场方法的有效性，进行特定于年龄和性别的研究。从参与者分析中可以得出结论，与本验证研究中使用的参考方法相比，调查现场方法的顺应性更高。
