Table 2.
Mean values measured, mean error, mean percentagage error, and mean absolute percentage error with related standard deviation for each parameter and tracker (N=20).
| Parameter | Mean (SD) | Mean error (SD) | MPEa (SD) | MAPEb (SD) | |
| Steps | |||||
| Fitbit | 10088.45 (5067.32) | 698.60 (1491.27) | 12.36 (18.26) | 17.05 (13.71) | |
| Garmin | 8834.85 (5067.07) | –555.00 (928.11) | –9.36 (18.55) | 12.90 (16.16) | |
| ActiGraph | 8375.70 (4716.39) | –1014.15 (846.81) | –11.53 (11.55) | 14.23 (7.76) | |
| Energy expenditure (cal) | |||||
| Fitbit | 2324.25 (547.02) | –175.70 (293.18) | –6.98 (12.67) | 12.26 (7.33) | |
| Garmin | 2434.65 (804.12) | –65.30 (682.94) | –2.09 (27.27) | 20.05 (18.04) | |
| NL2000i | 2102.30 (256.93) | –397.65 (306.13) | –14.61 (10.41) | 16.70 (6.3) | |
| MVPAc (min) | |||||
| Fitbit | 44.32 (45.83) | 12.63 (28.31) | 31.78 (103.51) | 75.74 (75.32) | |
| Garmin | 39.10 (57.18) | 13.80 (35.70) | 6.42 (109.75) | 91.98 (47.13) | |
| NL2000i | 20.30 (19.03) | –11.70 (18.45) | –41.43 (35.37) | 45.45 (29.67) | |
| TSTd (min) | |||||
| Fitbit | 389.83 (59.33) | 5.72 (49.11) | 2.27 (13.66) | 10.14 (9.12) | |
| Garmin | 442.83 (48.64) | 55.39 (48.07) | 15.85 (14.56) | 16.86 (13.3) | |
| WASOe (min) | |||||
| Fitbit | 49.21 (16.5) | 0.21 (22.15) | 25.02 (84.72) | 49.73 (72.03) | |
| Garmin | 13.14 (8.93) | –35.86 (22.13) | –66.89 (28.61) | 66.89 (28.61) | |
aMPE: mean percentage error.
bMAPE: mean absolute percentage error.
cMVPA: moderate-to-vigorous physical activity.
dTST: total sleep time.
eWASO: wake after sleep onset.