Department of Computer Science, Amsterdam University of Applied Sciences, 1091 GM Amsterdam, The Netherlands.
Human Media Interaction, University of Twente, 7522 NH Enschede, The Netherlands.
Sensors (Basel). 2018 May 22;18(5):1654. doi: 10.3390/s18051654.
Early detection of high fall risk is an essential component of fall prevention in older adults. Wearable sensors can provide valuable insight into daily-life activities; biomechanical features extracted from such inertial data have been shown to be of added value for the assessment of fall risk. Body-worn sensors such as accelerometers can provide valuable insight into fall risk. Currently, biomechanical features derived from accelerometer data are used for the assessment of fall risk. Here, we studied whether deep learning methods from machine learning are suited to automatically derive features from raw accelerometer data that assess fall risk. We used an existing dataset of 296 older adults. We compared the performance of three deep learning model architectures (convolutional neural network (CNN), long short-term memory (LSTM) and a combination of these two (ConvLSTM)) to each other and to a baseline model with biomechanical features on the same dataset. The results show that the deep learning models in a single-task learning mode are strong in recognition of identity of the subject, but that these models only slightly outperform the baseline method on fall risk assessment. When using multi-task learning, with gender and age as auxiliary tasks, deep learning models perform better. We also found that preprocessing of the data resulted in the best performance (AUC = 0.75). We conclude that deep learning models, and in particular multi-task learning, effectively assess fall risk on the basis of wearable sensor data.
早期发现高跌倒风险是预防老年人跌倒的重要组成部分。可穿戴传感器可以为日常生活活动提供有价值的见解; 从这些惯性数据中提取的生物力学特征已被证明对评估跌倒风险具有附加价值。例如,加速度计等可穿戴传感器可以为跌倒风险评估提供有价值的见解。目前,从加速度计数据中提取的生物力学特征用于评估跌倒风险。在这里,我们研究了机器学习中的深度学习方法是否适合从原始加速度计数据中自动提取评估跌倒风险的特征。我们使用了现有的 296 名老年人数据集。我们比较了三种深度学习模型架构(卷积神经网络(CNN)、长短期记忆(LSTM)和这两种模型的组合(ConvLSTM))彼此之间以及与具有生物力学特征的基线模型在同一数据集上的性能。结果表明,在单一任务学习模式下的深度学习模型在识别主体身份方面表现出色,但在跌倒风险评估方面,这些模型仅略优于基线方法。当使用多任务学习时,将性别和年龄作为辅助任务,深度学习模型的性能更好。我们还发现,对数据进行预处理可以实现最佳性能(AUC = 0.75)。我们得出结论,深度学习模型,特别是多任务学习,可以有效地根据可穿戴传感器数据评估跌倒风险。