Abstract
The ubiquity of wearable fitness trackers offers extensive opportunities for research on personal health. However, barriers specific to these trackers such as device abandonment and non-adherence often lead to substantial losses in data. As such, further research into adherence behaviors may derive the insights necessary to address these challenges and lead to more effective long-term studies. This paper serves to explore this approach: investigating the adherence behaviors of 617 college students belonging to a three-year observational study in which participants were monitored via Fitbit Charge HRs. Using this data, our objective was to assess the association between early adherence behaviors and device abandonment/long-term adherence. Adherence behavior from as early as participants' first 10 days in the study correlated with device abandonment and adherence over the next three years. Participants with unsatisfactory adherence in their first 30 days were twice as likely to abandon their devices and were, on average, 11% less adherent each month. The findings in this paper identify the stability of adherence behaviors, feasibility of their early detection and motivate the need to address non-adherent study participants early. Throughout these results, we discuss how the insights gathered from this work may shape the design of future long-term studies to minimize user attrition and promote prolonged engagement.