Wrist-worn consumer-grade activity trackers are popular devices, developed mainly for personal use. This study aimed to explore the validity, reliability and sensitivity to change of movement behaviors metrics from three activity trackers (Polar Vantage M, Garmin Vivoactive 4s and Garmin Vivosport) in controlled and free-living conditions when worn by older adults. Participants (n = 28; 74 ± 5 years) underwent a videotaped laboratory protocol while wearing all three trackers. On a separate occasion, participants (n = 17 for each of the trackers) wore one (randomly assigned) tracker and a research-grade activity monitor ActiGraph wGT3X-BT simultaneously for six consecutive days. Both Garmin trackers showed excellent performance for step counts, with a mean absolute percentage error (MAPE) below 20% and intraclass correlation coefficient (ICC_2,1) above 0.90 (p < 0.05). The MAPE for sleep time was within 10% for all the trackers tested, while it was far beyond 20% for all other movement behaviors metrics. The results suggested that all three trackers could be used for measuring sleep time with a high level of accuracy, and both Garmin trackers could also be used for step counts. All other output metrics should be used with caution. The results provided in this study could be used to guide choice on activity trackers aiming for different purposes—individual use, longitudinal monitoring or in clinical trial setting.

中文翻译：

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老年人受控和自由生活条件下三种消费级活动追踪器的适应性、可靠性和对变化的敏感性

腕戴式消费级活动追踪器是流行的设备，主要为个人使用而开发。本研究旨在探讨老年人佩戴时，在受控和自由生活条件下，三种活动追踪器（Polar Vantage M、Garmin Vivoactive 4s 和 Garmin Vivosport）对运动行为指标变化的有效性、可靠性和敏感性。参与者（n = 28；74 ± 5 岁）在佩戴所有三个跟踪器时接受了录像实验室协议。在另一个场合，参与者（每个跟踪器 n = 17）连续六天同时佩戴一个（随机分配的）跟踪器和研究级活动监视器 ActiGraph wGT3X-BT。两款 Garmin 追踪器在计步方面都表现出出色的性能，平均绝对百分比误差 (MAPE) 低于 20%，组内相关系数 (ICC)_2,1 ) 高于 0.90 ( p < 0.05)。所有测试的跟踪器的睡眠时间 MAPE 均在 10% 以内，而所有其他运动行为指标的 MAPE 则远远超过 20%。结果表明，所有三个跟踪器都可以用于高精度测量睡眠时间，并且两个 Garmin 跟踪器也可以用于计步。应谨慎使用所有其他输出指标。本研究提供的结果可用于指导针对不同目的（个人使用、纵向监测或临床试验设置）的活动跟踪器的选择。