Actigraph-defined moderate-to-vigorous physical activity cut-off points among children: statistical and biobehavioural relevance
Actigraph-defined moderate-to-vigorous physical activity cut-off points among children: statistical and biobehavioural relevance
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DOI：
10.1111/j.1651-2227.2008.01187.x
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发表时间：
2009-04-01
期刊：
影响因子：
3.8
通讯作者：
Hubert, Herve
中科院分区：
文献类型：
--
作者：
Guinhouya, Comlavi B.;Lemdani, Mohamed;Hubert, Herve
目的：比较Actigraph定义的中度到剧烈的体力活动（MVPA）的儿童cutpoints，结合统计和biobearninganalysis.Methods：一百一十三岁的儿童10.0 +/- 0.8岁戴加速度计三天。使用10个阈值估计他们在MVPA中花费的时间，范围从3000到3900 cpm。使用包括45个Bland和Altman成对分析的统计结构来比较MVPA的10个估计值。回归进行开发一个方程的平均差异之间的切点gaps.Results：平均差异MVPA估计范围从1.6到12.8分钟的增量的函数。MVPA的原始估计值根据算术顺序下降，其公差为200 cpm。这种差异导致MVPA下降了12%，并导致高达5%的儿童被错误分类。平均差异（Y）可以从增量（X）预测，使用：Y = 0.02 X（R-2 = 0.99，SEE = 0.72，p < 0.0001）。结论：当缺乏一致性时，应假设切割点间差距超过200 cpm，统计学差异可能在90 cpm时出现。然而，目前的公式使得有可能比较和调整的结果，从研究/干预措施使用不同的截断点的MVPA儿童。
Aim: To compare Actigraph-defined moderate-to-vigorous physical activity (MVPA) cutpoints among children, combining statistical and biobehavioural analyses.Methods: One hundred and thirteen children aged 10.0 +/- 0.8 years wore accelerometer for three days. The time they spent in MVPA was estimated using 10 thresholds ranged from 3000 to 3900 cpm. A statistical construct including 45 Bland and Altman pairwise analyses was used to compare the 10 estimates of MVPA. A regression was performed to develop an equation relating mean differences to the between-cutpoint gaps.Results: Mean differences in the MVPA estimates ranged from 1.6 to 12.8 min as a function of increment. Raw estimates of MVPA decreased according to an arithmetic sequence with a common difference of 200 cpm. This difference translates into a drop of 12% in MVPA and a misclassification of up to 5% of children. Mean differences (Y) could be predicted from increments (X) using: Y = 0.02 X (R-2 = 0.99, SEE = 0.72, p < 0.0001).Conclusion: When a lack of agreement should be assumed as the between-cutpoint gap exceeds 200 cpm, statistical differences may occur earlier at 90 cpm. Yet, the current equation makes it possible to compare and adjust results from studies/interventions using diverse cutpoints for MVPA among children.