Early Start Research Institute and Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, AUSTRALIA.
Med Sci Sports Exerc. 2018 Mar;50(3):609-616. doi: 10.1249/MSS.0000000000001449.
This study aimed to examine the validity of wrist acceleration cut points for classifying moderate (MPA), vigorous (VPA), and moderate-to-vigorous (MVPA) physical activity.
Fifty-seven children (5-12 yr) completed 15 semistructured activities. Three sets of wrist cut points (>192 mg, >250 mg, and >314 mg), previously developed using Euclidian norm minus one (ENMO192+), GENEActiv software (GENEA250+), and band-pass filter followed by Euclidian norm (BFEN314+), were evaluated against indirect calorimetry. Analyses included classification accuracy, equivalence testing, and Bland-Altman procedures.
All cut points classified MPA, VPA, and MVPA with substantial accuracy (ENMO192+: κ = 0.72 [95% confidence interval = 0.72-0.73], MVPA: area under the receiver operating characteristic curve (ROC-AUC) = 0.85 [0.85-0.86]; GENEA250+: κ = 0.75 [0.74-0.76], MVPA: ROC-AUC = 0.85 [0.85-0.86]; BFEN314+: κ = 0.73 [0.72-0.74], MVPA: ROC-AUC = 0.86 [0.86-0.87]). BFEN314+ misclassified 19.7% non-MVPA epochs as MPA, whereas ENMO192+ and GENEA250+ misclassified 32.6% and 26.5% of MPA epochs as non-MVPA, respectively. Group estimates of MPA time were equivalent (P < 0.01) to indirect calorimetry for the BFEN314+ MPA cut point (mean bias = -1.5%, limits of agreement [LoA] = -57.5% to 60.6%), whereas estimates of MVPA time were equivalent (P < 0.01) to indirect calorimetry for the ENMO192+ (mean bias = -1.1%, LoA = -53.7% to 55.9%) and GENEA250+ (mean bias = 2.2%, LoA = -56.5% to 52.2%) cut points. Individual variability (LoA) was large for MPA (min: BFEN314+, -60.6% to 57.5%; max: GENEA250+, -42.0% to 104.1%), VPA (min: BFEN314+, -238.9% to 54.6%; max: ENMO192+, -244.5% to 127.4%), and MVPA (min: ENMO192+, -53.7% to 55.0%; max: BFEN314+, -83.9% to 25.3%).
Wrist acceleration cut points misclassified a considerable proportion of non-MVPA and MVPA. Group-level estimates of MVPA were acceptable; however, error for individual-level prediction was larger.
本研究旨在检验手腕加速度切点分类中度（MPA）、剧烈（VPA）和中高强度（MVPA）身体活动的有效性。
57 名儿童（5-12 岁）完成了 15 项半结构化活动。先前使用欧几里得范数减一（ENMO192+）、GENEActiv 软件（GENEA250+）和带通滤波器后欧几里得范数（BFEN314+）开发的三组手腕切点（>192mg、>250mg 和>314mg）与间接测热法进行了评估。分析包括分类准确性、等效性检验和 Bland-Altman 程序。
所有切点均以较大的准确性对 MPA、VPA 和 MVPA 进行了分类（ENMO192+：κ=0.72[95%置信区间=0.72-0.73]，MVPA：受试者工作特征曲线下面积（ROC-AUC）=0.85[0.85-0.86]；GENEA250+：κ=0.75[0.74-0.76]，MVPA：ROC-AUC=0.85[0.85-0.86]；BFEN314+：κ=0.73[0.72-0.74]，MVPA：ROC-AUC=0.86[0.86-0.87]）。BFEN314+ 将 19.7%的非 MVPA 时间错误分类为 MPA，而 ENMO192+和 GENEA250+分别将 32.6%和 26.5%的 MPA 时间错误分类为非 MVPA。BFEN314+ 的 MPA 切点的群体估计（P<0.01）与间接测热法相当（平均偏差=-1.5%，界限范围[LoA]=-57.5%至 60.6%），而 ENMO192+（平均偏差=-1.1%，LoA=-53.7%至 55.9%）和 GENEA250+（平均偏差=2.2%，LoA=-56.5%至 52.2%）切点的 MVPA 时间估计与间接测热法相当。MPA（最小：BFEN314+，-60.6%至 57.5%；最大：GENEA250+，-42.0%至 104.1%）、VPA（最小：BFEN314+，-238.9%至 54.6%；最大：ENMO192+，-244.5%至 127.4%）和 MVPA（最小：ENMO192+，-53.7%至 55.0%；最大：BFEN314+，-83.9%至 25.3%）的个体变异性（LoA）较大。
手腕加速度切点错误分类了相当一部分非 MVPA 和 MVPA。MVPA 的群体水平估计是可以接受的；然而，个体水平预测的误差更大。
