Bent Brinnae, Goldstein Benjamin A, Kibbe Warren A, Dunn Jessilyn P
1Department of Biomedical Engineering, Duke University, Durham, NC USA.
2Department of Bioinformatics and Biostatistics, Duke University, Durham, NC USA.
NPJ Digit Med. 2020 Feb 10;3:18. doi: 10.1038/s41746-020-0226-6. eCollection 2020.
As wearable technologies are being increasingly used for clinical research and healthcare, it is critical to understand their accuracy and determine how measurement errors may affect research conclusions and impact healthcare decision-making. Accuracy of wearable technologies has been a hotly debated topic in both the research and popular science literature. Currently, wearable technology companies are responsible for assessing and reporting the accuracy of their products, but little information about the evaluation method is made publicly available. Heart rate measurements from wearables are derived from photoplethysmography (PPG), an optical method for measuring changes in blood volume under the skin. Potential inaccuracies in PPG stem from three major areas, includes (1) diverse skin types, (2) motion artifacts, and (3) signal crossover. To date, no study has systematically explored the accuracy of wearables across the full range of skin tones. Here, we explored heart rate and PPG data from consumer- and research-grade wearables under multiple circumstances to test whether and to what extent these inaccuracies exist. We saw no statistically significant difference in accuracy across skin tones, but we saw significant differences between devices, and between activity types, notably, that absolute error during activity was, on average, 30% higher than during rest. Our conclusions indicate that different wearables are all reasonably accurate at resting and prolonged elevated heart rate, but that differences exist between devices in responding to changes in activity. This has implications for researchers, clinicians, and consumers in drawing study conclusions, combining study results, and making health-related decisions using these devices.
随着可穿戴技术越来越多地用于临床研究和医疗保健，了解其准确性并确定测量误差如何影响研究结论以及对医疗决策产生影响至关重要。可穿戴技术的准确性在研究文献和科普文献中一直是一个备受争议的话题。目前，可穿戴技术公司负责评估和报告其产品的准确性，但关于评估方法的公开信息却很少。可穿戴设备的心率测量来自光电容积脉搏波描记法（PPG），这是一种测量皮肤下血容量变化的光学方法。PPG中潜在的不准确之处主要源于三个主要方面，包括（1）不同的皮肤类型、（2）运动伪影和（3）信号交叉。迄今为止，尚无研究系统地探讨过不同肤色人群使用可穿戴设备时的准确性。在此，我们在多种情况下探索了消费级和研究级可穿戴设备的心率和PPG数据，以测试这些不准确之处是否存在以及存在的程度。我们发现不同肤色人群在准确性方面没有统计学上的显著差异，但不同设备之间以及不同活动类型之间存在显著差异，特别是活动期间的绝对误差平均比休息时高30%。我们的结论表明，不同的可穿戴设备在静息和心率长期升高时都具有合理的准确性，但在对活动变化的响应方面，不同设备之间存在差异。这对研究人员、临床医生和消费者在得出研究结论、整合研究结果以及使用这些设备做出与健康相关的决策方面都有影响。
