Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal.
ICVS/3B's, PT Government Associate Laboratory, 4710-057 Braga/Guimarães, Portugal.
Sensors (Basel). 2021 Mar 24;21(7):2258. doi: 10.3390/s21072258.
Accurate assessment of physical activity (PA) is crucial in interventions promoting it and in studies exploring its association with health status. Currently, there is a wide range of assessment tools available, including subjective and objective measures. This study compared accelerometer-based estimates of PA with self-report PA data in older adults. Additionally, the associations between PA and health outcomes and PA profiles were analyzed. Participants ( = 110) wore a Xiaomi Mi Band 2 for fifteen consecutive days. Self-reported PA was assessed using the International Physical Activity Questionnaire (IPAQ) and the Yale Physical Activity Survey (YPAS). The Spearman correlation coefficient was used to compare self-reported and accelerometer-measured PA and associations between PA and health. Bland-Altman plots were performed to assess the agreement between methods. Results highlight a large variation between self-reported and Xiaomi Mi Band 2 estimates, with poor general agreement. The highest difference was found for sedentary time. Low positive correlations were observed for IPAQ estimates (sedentary, vigorous, and total PA) and moderate for YPAS vigorous estimates. Finally, self-reported and objectively measured PA associated differently with health outcomes. Summarily, although accelerometry has the advantage of being an accurate method, self-report questionnaires could provide valuable information about the context of the activity.
准确评估身体活动 (PA) 对于促进身体活动的干预措施以及研究其与健康状况的关系至关重要。目前，有广泛的评估工具可供选择，包括主观和客观测量。本研究比较了基于加速度计的 PA 估计值与老年人的自我报告 PA 数据。此外，还分析了 PA 与健康结果和 PA 特征之间的关联。参与者（n=110）连续佩戴小米手环 2 十五天。使用国际体力活动问卷 (IPAQ) 和耶鲁体力活动调查 (YPAS) 评估自我报告的 PA。采用 Spearman 相关系数比较自我报告和加速度计测量的 PA 以及 PA 与健康之间的关联。Bland-Altman 图用于评估方法之间的一致性。结果表明，自我报告和小米手环 2 估计值之间存在较大差异，总体一致性较差。久坐时间的差异最大。IPAQ 估计值（久坐、剧烈和总 PA）的相关性较低，而 YPAS 剧烈估计值的相关性适中。最后，自我报告和客观测量的 PA 与健康结果的关联不同。总之，尽管加速度计具有准确性高的优点，但自我报告问卷可以提供有关活动背景的有价值信息。
