Table 5. Monitor-specific wrist Euclidean Norm Minus One (ENMO (measured in milligravity units)) thresholds to differentiate between sedentary behaviours and light-intensity physical activities.
| Monitor Placement: Wrist | Discrimination | |||||
|---|---|---|---|---|---|---|
| Sedentary Behaviours | ||||||
| vs. | ||||||
| Standing Still | Washing Pots | Dusting | Sweeping Floor | Self-Paced Free-Living Walk | ||
| ENMO Threshold (milligravity) | AG | 5.7 | 25.8 | 27.9 | 52.5 | 41.4 |
| GA | 8.7 | 30.7 | 34.4 | 52.6 | 47.1 | |
| Sensitivity (%) | AG | 79% | 94% | 94% | 91% | 91% |
| GA | 70% | 97% | 100% | 100% | 100% | |
| Specificity (%) | AG | 45% | 93% | 94% | 99% | 99% |
| GA | 43% | 99% | 99% | 100% | 100% | |
| ENMO AUROC † (95% CI) | AG | 0.601 (0.520, 0.682) | 0.965 (0.928, 1.000) | 0.963 (0.913, 1.000) | 0.952 (0.887, 1.000) | 0.966 (0.920, 1.000) |
| GA | 0.468 (0.381, 0.555) | 0.994 (0.986, 1.000) | 0.999 (0.996, 1.000) | 1.000 (1.000, 1.000) | 1.000 (1.000, 1.000) | |
| ENMO LOOCV AUROC ‡ (95% CI) | AG | 0.337 (0.238, 0.436) | 0.957 (0.907, 1.000) | 0.955 (0.896, 1.000) | 0.938 (0.855, 1.000) | 0.950 (0.886, 1.000) |
| GA | 0.383 (0.306, 0.451) | 0.992 (0.981, 1.000) | 0.998 (0.994, 1.000) | 1.000 (1.000, 1.000) | 1.000 (1.000, 1.000) | |
Sedentary behaviours = any form of lying plus any form of sitting (activities 1 to 11); ENMO = Euclidean Norm Minus One (measured in milligravity units); AG = ActiGraph GT3X+ accelerometer; GA = GENEActiv accelerometer
† Area under Receiver-Operating-Characteristic curve
‡ Leave-One-Out-Cross-Validation Area under Receiver-Operating-Characteristic curve