Supplementary Material for: Continuous Digital Assessment for Weight Loss Surgery Patients

We conducted a survey about recent surgical procedures on a large connected population and requested each individual’s permission to access data from commercial wearable devices they may have been wearing around the time of the procedure. For subcohorts of 66–118 patients who reported having a weight loss procedure and who had dense Fitbit data around their procedure date, we examined several daily measures of behavior and physiology in the 12 weeks leading up to and the 12 weeks following their procedures. We found that the weeks following weight loss operations were associated with fewer daily total steps, smaller proportions of the day spent walking, lower resting and 95th percentile heart rates, more total sleep time, and greater sleep efficiency. We demonstrate that consumer-grade activity trackers can capture behavioral and physiological changes resulting from weight loss surgery and these devices have the potential to be used to develop measures of patients’ postoperative recovery that are convenient, sensitive, scalable, individualized, and continuous.