Validating Room Location within the Home for Functional Measures from Digital Health Technologies.

Digital health technologies have the potential to measure how a patient feels and functions with low patient burden e.g.: to provide real-world evidence of the benefit of a novel treatment. Despite this potential, traditional wearable devices, e.g. actigraphy, do not provide location-activity information which may improve the validity of these measures relative to established clinical measures. We describe a system that combines a wearable bracelet with Bluetooth-low-energy environment beacons to help localize and provide environmental context to that wearable data, and therefore provide a more clinically relevant measure of function. We describe an initial validation of the accuracy of the location information provided by this system in a study of 5 different real living environments of different size and layout, each collecting data over multiple days and recording their actual location in their home every 15 minutes in a diary. The results are presented in a confusion matrix. Mean overall accuracy was 94.0% (range 88.8-98.8%), which is sufficient to enable construction of more meaningful outcomes for patients than activity alone. For example, to determine if someone is moving around their home more, if they are getting outside more, if they are spending more time in bed, etc. It may be possible to improve location accuracy further with more sophisticated analysis of the beacon data.