Who Uses Wearable Activity Trackers and Why? A Comparison of Former and Current Users in the United States.

<bold>Background: </bold>There has been an explosion in the use of wearable activity trackers (WATs), but we do not fully understand who wears them and why. This study's purpose was to describe the characteristics of WAT users and to compare current and former users.<bold>Materials and Methods: </bold>A variety of internet-based resources (eg, Craigslist, Facebook) were used to recruit current and former WAT users. Respondents completed a web-based survey, where they provided information on sociodemographic characteristics, health, physical activity behavior, and about their WAT use.<bold>Results: </bold>Of the 2826 respondents who gave informed consent, 70.8% (n = 2002) met inclusion criteria for this analysis. Respondents ranged from 18 to 81 years old (mean 32.9 ± 12.2 standard deviation) with 73.8% women. Most were current WAT users (68.7%), and the average length of WAT use overall was 9.3 ± 9.7 months. On average, current users wore the device for 3.7 months longer than former users. Compared to current users, former users had a lower body mass index (1.2 kg/m2 less), reported fewer medical conditions, shared data from their device less often, and received the device as a gift more frequently.<bold>Conclusions: </bold>Current and former users varied in their reasons for using a WAT and how they used their device. Differences identified between these groups support further exploration of associations between WAT users' profiles and their physical activity behavior. [ABSTRACT FROM AUTHOR]