Eke Helén, Bonn Stephanie E, Trolle Lagerros Ylva
Department of Medicine (Solna) Clinical Epidemiology Division, Karolinska Institutet Stockholm Sweden.
Center for Obesity, Academic Specialist Center, Stockholm Health Services Stockholm Sweden.
Health Sci Rep. 2024 Jan 10;7(1):e1810. doi: 10.1002/hsr2.1810. eCollection 2024 Jan.
Accelerometers collect data in an objective way, however, a number of decisions must be done during data collection, processing and output-interpretation. The influence of those decisions is seldom investigated, reported, or discussed. Herein, we examined the influence of different decisions on the outcomes: daily minutes of moderate-to-vigorous physical activity (MVPA), inactivity and light physical activity (LPA).
In total, 156 participants wore an accelerometer (ActiGraph wGT3X-BT) on their nondominant wrist for 7 days. Data collection was conducted from February 2017 to June 2018. Data was processed using the R-package GGIR and default settings were compared to by-the-literature-suggested options. The output was examined using paired -tests.
When comparing two commonly used MVPA-cut-points, default and Hildebrand et al. we found a marginal difference (0.4 min, 1.0%, < 0.001) in MVPA/day. When no bout criteria for MVPA/day was applied, MVPA/day was twice as high as bouted MVPA/day. Further, when we changed the epoch-length from 5 to 1 s, statistically significant changes were seen for MVPA/day (-6.6 min, 19%, < 0.001), inactivity/day (-22 min, 3.0%, < 0.001) and LPA/day (28 min, 81%, < 0.001).
Decisions made during data processing of wrist-worn accelerometers has an influence on the output and thus, may influence the conclusions drawn. However, there may be situations when these settings are changed. If so, we recommend examining if the variables of interest are affected. We encourage researchers to report decisions made during data collection, processing and output-interpretation, to facilitate comparisons between different studies.
加速度计以客观的方式收集数据，然而，在数据收集、处理和输出解释过程中必须做出许多决策。这些决策的影响很少被研究、报道或讨论。在此，我们研究了不同决策对结果的影响：中度至剧烈身体活动（MVPA）、不活动和轻度身体活动（LPA）的每日分钟数。
共有156名参与者在其非优势手腕上佩戴加速度计（ActiGraph wGT3X - BT）7天。数据收集于2017年2月至2018年6月进行。使用R包GGIR处理数据，并将默认设置与文献建议的选项进行比较。使用配对检验检查输出结果。
比较两个常用的MVPA切点（默认值和希尔德布兰德等人提出的值）时，我们发现MVPA/天存在微小差异（0.4分钟，1.0%，<0.001）。当不应用MVPA/天的发作标准时，MVPA/天是有发作标准的MVPA/天的两倍。此外，当我们将时间间隔从5秒改为1秒时，MVPA/天（-6.6分钟，19%，<0.001）、不活动/天（-22分钟，3.0%，<0.001）和LPA/天（28分钟，81%，<0.001）出现了统计学上的显著变化。
手腕佩戴式加速度计数据处理过程中做出的决策会影响输出结果，因此可能会影响得出的结论。然而，在某些情况下可能会更改这些设置。如果是这样，我们建议检查感兴趣的变量是否受到影响。我们鼓励研究人员报告在数据收集、处理和输出解释过程中做出的决策，以便于不同研究之间的比较。
