Accuracy and Acceptability of Commercial-Grade Physical Activity Monitors in Older Adults

Abstract

The aim of this study was to evaluate accuracy of seven commercial activity monitors in measuring steps in older adults with varying walking abilities and to assess monitor acceptability and usability. Forty-three participants (age = 87 ± 5.7 years) completed a gait speed assessment, two walking trials while wearing the activity monitors, and questionnaires about usability features and activity monitor preferences. The Accusplit AX2710 Accelerometer Pedometer had the highest accuracy (93.68% ± 13.95%), whereas the Fitbit Charge had the lowest (39.12% ± 40.3%). Device accuracy varied based on assistive device use, and none of the monitors were accurate at gait speeds <0.08 m/s. Barriers to monitor usability included inability to apply monitor and access the step display. Monitor accuracy was rated as the most important feature, and ability to interface with a smart device was the least important feature. This study identified the limitations of the current commercial activity monitors in both step counting accuracy and usability features for older adults.

Keywords: accuracy; gait speed; pedometer; step count; walking.

Figure 1 —

Overall percentage accuracy^a of activity monitors. ^aAccuracy was defined as monitor steps/observed steps × 100 with 100% indicating perfect accuracy.

Figure 2 —

Percent of participants reporting a favorable usability rating for the activity monitor. Favorable rating = rating of a 4 or 5 on a 5-point Likert scale.

Figure 3 —

Important features of activity monitors based on participant ratings (mean rating).