Table 1.
Percentages of agreement for 3 stages of sleep scoring (awake/light sleep/deep sleep) between the gold standard (PSG) and the scoring of MB and SC.
| PSG Gold Standard | |||
|---|---|---|---|
| WAKE | LIGHT SLEEP | DEEP SLEEP | |
| Mi Band (MB) staging | |||
| Wake | |||
| % Sensitivity | 5.5 | 0.1 | 1.5 |
| % PPV | 62.8 | 4.7 | 32.6 |
| Light sleep | |||
| % Sensitivity | 79.2 | 70.6 | 51.3 |
| % PPV | 18.9 | 57.8 | 23.2 |
| Deep sleep | |||
| % Sensitivity | 15.3 | 29.3 | 47.2 |
| % PPV | 7.5 | 48.9 | 43.6 |
| Sleep Cycle (SC) staging | |||
| Wake | |||
| % Sensitivity | 55.6 | 37.0 | 16.9 |
| % PPV | 24.3 | 61.1 | 14.7 |
| Light sleep | |||
| % Sensitivity | 36.4 | 40.9 | 31.1 |
| % PPV | 14.4 | 61.2 | 24.4 |
| Deep sleep | |||
| % Sensitivity | 8.0 | 22.1 | 52.0 |
| % PPV | 4.1 | 42.8 | 53.0 |
| Devices/applications | OA (%) | K/PABAK | |
| Mi Band | |||
| MB | 53.31 | 0.14/0.06 | |
| Sleep Cycle | |||
| SC | 46.34 | 0.18/−0.07 | |
The agreement is demonstrated by the means of sensitivity (%) as well as by the positive predictive value (PPV). The percentage of overall agreement (OA; %), Cohen’s Kappa coefficient (K) and Prevalence-adjusted Bias-adjusted Kappa (PABAK) are reported for each device.