Fig. 2

Effect of wear location on overall accuracy (mean absolute percentage error, MAPE) of wearable technologies’ step counting ability. MAPE and corresponding 95% confidence intervals (CIs; estimated using mixed effect models) of each wear location are presented at slow, normal, and fast walking speed levels. Slow speed bouts: 0.8, 1.6, 2.4, 3.2 km/h (0.5, 1.0, 1.5, 2.0 mph); normal speed bouts: 4.0, 4.8, 5.6, 6.4 km/h (2.5, 3.0, 3.5, 4.0 mph); fast speed bouts: 7.2, 8.0 km/h (4.5, 5.0 mph). MAPE values were averaged across devices respective to each wear location for slow, normal, and fast walking speeds. MAPE values closer to 0 are indicative of greater accuracy. Further, where 95% CIs do not overlap, there are significant differences between locations. Likelihood ratio test P value is reported for the effect of wear location on MAPE for each specific speed level