Fig. 1: Study overview.
From: Real-time alerting system for COVID-19 and other stress events using wearable data
a, Participants with a Fitbit and/or Apple Watch were asked to share their wearable and survey data using the study mobile app MyPHD. The app securely transfers the de-identified data (heart rates, steps and survey events) to the back-end for real-time analysis. On the back-end, three online infection detection algorithms were deployed, and the results from one of the algorithms (online NightSignal) were returned to the participants using the app: red alerts indicate abnormal changes in overnight RHR; green alerts indicate normal overnight RHR. b, A real-world example of real-time pre-symptomatic detection of COVID-19 using the online NightSignal algorithm for a participant using an Apple Watch. Alerts were triggered 2 d before the symptom onset date and continued until 3 d after the diagnosis date.
