JMIR Publications

ABSTRACT

Background:

Commercial off-the-shelf activity trackers (e.g., Fitbit) allow users to self-monitor their daily activity, including number of steps, type of PA, and amount of sleep, among other features. Fitbits have been used as both measurement and intervention tools. However, it is not clear how they are being incorporated into PA intervention studies, and differences in use protocols across the life course (e.g., models, strategies to boost wear time) are not known.

Objective:

This paper aimed to review the use of Fitbit devices in PA intervention research across the life course in order to provide intervention scientists with a synthesis of information that may inform their future trials involving Fitbit devices.

Methods:

We conducted a search of the Fitabase Fitbit Research Library. Of the 682 studies available on the Fitabase Fitbit Research Library, 79 interventions met the eligibility criteria for this review and 44 were selected for inclusion, representing interventions conducted in childhood, adolescence, early, middle, and older adulthood.

Results:

Most studies used developmentally appropriate behavior change techniques and wear time instructions. Device wear instructions differed substantially across studies, ranging from a specific number of hours over a given assessment period to daily wear for the duration of the intervention. Strategies to boost wear time included daily reminders through texts and syncing Fitbit data. Minimum wear time criteria differed considerably, both within and between developmental stages. Additionally, rates of adherence to wear time criteria were reported using varying metrics. Most studies supplemented the use of Fitbits with additional objective or self-report measures for PA.

Conclusions:

Future work should focus on developing standardized protocols for using commercially available devices, especially the most popular ones, in the context of research.