BACKGROUND Pooling data from thigh-worn accelerometers across multiple studies has great potential to advance evidence on the health benefits of physical activity. This requires harmonization of information on body postures, physical activity types, volumes and time patterns across different brands of devices. The aim of this study is to compare the physical behavior estimates provided by three different brands of thigh-worn accelerometers. METHODS Twenty participants volunteered for a 7-day free-living measurement. Three accelerometers - ActiGraph GT3X+, Axivity AX3 and ActivPAL Micro4 - were randomly placed in a vertical line on the midsection of the right thigh. Raw data from each accelerometer was processed and classified into 8 physical activities and postures using the Acti4 software. Absolute differences between estimates and the respective coefficient of variation (CV) were calculated. RESULTS We observed very minor differences between physical behavior estimates from three different accelerometer brands. When averaged over 24 h (1,440 min), the absolute difference (CV) between accelerometers were: 1.2 mins (0.001) for lying/sitting, 3.4 mins (0.02) for standing, 3.5 mins (0.06) for moving, 1.9 mins (0.03) for walking, 0.1 mins (0.19) for running, 1.2 mins (0.19) for stair climbing, 1.9 mins (0.07) for cycling. Moreover, there was an average absolute difference of 282 steps (0.03) per 24 h. CONCLUSIONS Physical behaviors were classified with negligible difference between the accelerometer brands. These results support harmonization of data from different thigh-worn accelerometers across multiple cohorts when analyzed in an identical manner.

中文翻译：

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三种不同的大腿加速计品牌的身体行为估计值的比较：预期身体活动，坐着和睡眠联盟（ProPASS）的概念证明。

背景技术跨多个研究收集来自大腿加速计的数据具有巨大的潜力，可以促进有关体育锻炼对健康有益的证据。这要求在不同品牌的设备上协调有关身体姿势，体育活动类型，数量和时间模式的信息。这项研究的目的是比较三种不同品牌的大腿加速计提供的身体行为估计。方法二十名参与者自愿参加了为期7天的自由生活评估。将三个加速度计-ActiGraph GT3X +，Axivity AX3和ActivPAL Micro4-随机放置在右大腿中部的垂直线上。使用Acti4软件处理来自每个加速度计的原始数据，并将其分类为8种身体活动和姿势。计算了估算值与各自的变异系数（CV）之间的绝对差。结果我们观察到来自三个不同加速度计品牌的身体行为估计之间的微小差异。当平均24小时（1,440分钟）时，加速度计之间的绝对差（CV）为：躺着/坐着的时间为1.2分钟（0.001），站立时为3.4分钟（0.02），移动时为3.5分钟（0.06），1.9分钟（0.03） ）步行；跑步0.1分钟（0.19）；爬楼梯1.2分钟（0.19）；骑自行车1.9分钟（0.07）。此外，每24小时平均有282步（0.03）的绝对绝对差。结论加速度计品牌之间的身体行为分类差异可忽略不计。