Fig. 1

Effect of speed on overall accuracy (mean absolute percentage error, MAPE) of wearable technology’s step counting ability. Participants walked on a treadmill for 5-min bouts beginning at 0.8 km/h (0.5 mph) and increasing in 0.8 km/h (0.5 mph). MAPE and corresponding 95% confidence intervals (CIs) respective to each technology are plotted across speed bouts. Each point represents grouped averages of MAPE values, with 95% CIs estimated using mixed effect models and extending above and below that point estimate. MAPE values closer to 0 are indicative of greater accuracy. Further, where 95% CIs do not overlap, there are significant differences between speed bouts. Likelihood ratio test P value is reported for the effect of all speeds on MAPE for each specific device