可穿戴技术在测量身体活动(PA)和促进健康方面发挥着重要作用。标准化验证指数(即,准确度,偏见,和精度)比较计步可穿戴技术在年轻人中的表现。
为在不同跑步机速度(慢速[0.8-3.2km/h],正常[4.0-6.4km/h],快速[7.2-8.0公里/小时]),磨损位置(腰部,手腕/手臂,大腿,和脚踝),和年龄组(儿童,6-12岁;青少年,13-17岁;年轻人,18-20年)。
一百一十七个人(13.1±4.2岁,50.4%的女性)参加了这项横断面研究,并在穿着八种设备时完成了5分钟的跑步机比赛(0.8km/h至8.0km/h)(腰部:动作,ActiGraphGT3X+,NL-1000,SW-200;手腕:ActiGraphGT3X;手臂:SenseWear;大腿:activPAL;脚踝:StepWatch)。直接观察到的步骤作为标准度量。准确度(平均绝对百分比误差,地图),偏差(平均百分比误差,MPE),和精度(相关系数,r;标准偏差,标准差;变异系数,CoV)进行了计算。
八种经过测试的可穿戴技术中的五种(即,Actical,腰部佩戴的ActiGraphGT3X+,activPAL,StepWatch,和SW-200)在正常速度范围内以<5%的MAPE进行。更一般地说,腰围(MAPE=4%),在正常速度下,大腿(4%)和脚踝(5%)位置的准确性高于手腕位置(23%)。平均而言,所有可穿戴技术在低速下显示的精度最低(MAPE=50.1±35.5%),和最高的精度在正常速度(MAPE=15.9±21.7%)。速度和磨损位置对精度和偏差有显著影响(P<0.001),但对精度没有影响(P>0.05)。年龄没有影响(P>0.05)。
标准化的验证指标侧重于准确性,偏见,精度是按速度分类的,磨损位置,和年龄组在选择和/或评估年轻人的设备性能时作为重要的参考点。对于所有设备,在非常缓慢的步行速度(0.8至3.2km/h)下,可能会降低性能。脚踝磨损和大腿磨损的设备显示出最高的准确性。速度和磨损位置对精度和偏差有显著影响,但不是精确。
Clinicaltrials.govNCT01989104。2013年11月14日注册
Wearable technologies play an important role in measuring physical activity (PA) and promoting health. Standardized validation indices (i.e., accuracy, bias, and precision) compare performance of step counting wearable technologies in young people.
To produce a catalog of validity indices for step counting wearable technologies assessed during different treadmill speeds (slow [0.8-3.2 km/h], normal [4.0-6.4 km/h], fast [7.2-8.0 km/h]), wear locations (waist, wrist/arm, thigh, and ankle), and age groups (children, 6-12 years; adolescents, 13-17 years; young adults, 18-20 years).
One hundred seventeen individuals (13.1 ± 4.2 years, 50.4% female) participated in this cross-sectional study and completed 5-min treadmill bouts (0.8 km/h to 8.0 km/h) while wearing eight devices (Waist: Actical, ActiGraph GT3X+, NL-1000, SW-200; Wrist: ActiGraph GT3X+; Arm: SenseWear; Thigh: activPAL; Ankle: StepWatch). Directly observed steps served as the criterion measure. Accuracy (mean absolute percentage error, MAPE), bias (mean percentage error, MPE), and precision (correlation coefficient, r; standard deviation, SD; coefficient of variation, CoV) were computed.
Five of the eight tested wearable technologies (i.e., Actical, waist-worn ActiGraph GT3X+, activPAL, StepWatch, and SW-200) performed at < 5% MAPE over the range of normal speeds. More generally, waist (MAPE = 4%), thigh (4%) and ankle (5%) locations displayed higher accuracy than the wrist location (23%) at normal speeds. On average, all wearable technologies displayed the lowest accuracy across slow speeds (MAPE = 50.1 ± 35.5%), and the highest accuracy across normal speeds (MAPE = 15.9 ± 21.7%). Speed and wear location had a significant effect on accuracy and bias (P < 0.001), but not on precision (P > 0.05). Age did not have any effect (P > 0.05).
Standardized validation indices focused on accuracy, bias, and precision were cataloged by speed, wear location, and age group to serve as important reference points when selecting and/or evaluating device performance in young people moving forward. Reduced performance can be expected at very slow walking speeds (0.8 to 3.2 km/h) for all devices. Ankle-worn and thigh-worn devices demonstrated the highest accuracy. Speed and wear location had a significant effect on accuracy and bias, but not precision.
Clinicaltrials.gov NCT01989104 . Registered November 14, 2013.