Table 1.
Study efficacy endpoints, comparator device used for associated endpoint data collection, and statistical agreement between investigational device and comparator on an overall and activity grouped basis
| Efficacy endpoint | Comparator device | Overall observed range | Overall comparison (sleep, resting, moving) | Sleep comparison | Resting comparison | Moving comparison |
|---|---|---|---|---|---|---|
| HR | Actiheart | 38–136 bpm | corr. = 0.957, MAE = 2.0±5.1 bpm | corr. = 0.865, MAE = 1.9±5.3 bpm | corr. = 0.947, MAE = 1.9±4.0 bpm | corr. = 0.900, MAE = 2.3±5.9 bpm |
| HRV (RMSSD) | Actiheart | 2.32–747.24 ms | corr. = 0.965, MAE = 5.056±24.907 ms | corr. = 0.939, MAE = 10.09±38.20 ms | corr. = 0.977, MAE = 3.41±18.13 ms | corr. = 0.996, MAE = 1.67±6.23 ms |
| HRV ratio (LF/HF) | Actiheart | 0.2–30.5 | corr. = 0.861, MAE = 1.09±1.82 | corr. = 0.845, MAE = 0.67±1.44 | corr. = 0.825, MAE = 1.34±2.06 | corr. = 0.892, MAE = 1.27±1.84 |
| RR | Capno-stream35 | 3–4 breaths/min | N/A | corr. = 0.697, MAE = 1.3±2.1 breaths/min | N/A | N/A |
| Step count | independent observer with manual counter | 467–716 steps/6 min | N/A | N/A | N/A | walking only, corr. = 0.950, MAE = 14.7±11.9 steps, error = 2.5% (average ground truth = 598.7 steps) |
The HRV ratio for sleep was calculated using all qualified data pairs. corr., correlation; HF, high frequency; HR, heart rate; HRV, heart rate variability; LF, low frequency; MAE, mean absolute error; RMSSD, root mean square of successive differences; RR, respiration rate.