Figure 4
From: Passive longitudinal weight and cardiopulmonary monitoring in the home bed
Respiratory monitoring using non-contact adherence-independent BedScales. (a) Raw respiratory signals from 4 scales in the middle of an overnight recording (light gray is the entire overnight weight signal). (b) Composite signal (purple) derived from linear combination of scales weighted by PCA-based eigenvalues compared to commercial respiratory chest belt (black) with peak finding annotation (green and blue dots respectively) across short (top) and long (bottom) time scales. Inset shows short inspiratory phase with rapid linear increase during inspiration followed by longer exponential decay during passive expiration. (c) Comparison of respiratory rates derived from BedScales (purple) and commercial respiratory chest belt (black) across one night (~ 1000 epochs). (d) Histogram of respiratory rate differences between BedScales and a commercial respiratory chest belt across 8 sleep study patients. X axis limits set at ± 1% quantile of error. (e) Bland–Altman plot comparing BedScales and chest belt respiratory rates. Y axis limits set at ± 1% quantile of error.
