ACCURACY AND RELIABILITY OF A CONSUMER-GRADE ACTIVITY TRACKER AMONG OLDER PEOPLE: A PILOT STUDY

Catherine Patrick*1, Michael A. SmithƗ1, Antonio Harris*1 and Melissa Powersǂ1. 1University of Central Oklahoma, Edmond, Oklahoma Activity trackers are popular devices used to track and encourage physical activity; although the accuracy of activity trackers among older people is unknown. PURPOSE: The purpose of this pilot study was to evaluate the accuracy and reliability of step counts from a consumer-grade activity tracker by comparing step counts to a research-grade accelerometer and video recording. METHODS: Seven volunteers (mean age = 69.57±3.65 years) agreed to participate. Two participants did not complete the second round of testing. Researchers collected height, weight, and age. The activity tracker and accelerometer were set-up using manufacturer’s procedures. Participants wore the activity tracker and accelerometer as they walked 96 meters around an indoor gym floor at their normal walking pace. The walk was also video recorded to determine observational step count confirmed by two researchers. The same procedures were repeated on a second, non-consecutive day. Data collected from the activity tracker were compared to the accelerometer and observed step count. In addition, step counts from the first walk were compared to step counts from the second walk. RESULTS: At the first walk, the activity tracker was found to significantly underestimate step counts by 18.86 steps when compared to the observed step count, t (6) = -3.27, p = .017. The activity tracker step count was not different than the accelerometer step count. At the second walk, no differences in step counts were observed between the activity tracker and the accelerometer or the observed step count (p \u3e .05). In addition, no differences in step counts were observed between walk 1 and walk 2 using the activity tracker, accelerometer, and observed step count. CONCLUSION: Although preliminary, these data indicate fair accuracy and good reliability of a consumer-grade activity tracker when compared to the accelerometer and observed step count. We suggest this pilot study be extended to include additional participants and comparisons of other activity trackers. Activity trackers are widely used to measures physical activity, but their accuracy and reliability remains questionable especially among older people. Additionally, new products and upgrades are made available so quickly that research on the accuracy and reliability of these devices is difficult to obtain