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Quantitative sleep analysis through the use of polysomnography is a well established standard. Finding new ways to approach this, especially over multiple nights, is becoming more important due to a growing recognition of adverse effects from poor sleep and sleep disorders. The Non-Invasive Analysis of Physiological Signals (NAPSTM) system is a ballistocardiography-based monitoring system developed to measure heart rate, breathing rate and musculoskeletal movement that shows promise as a general sleep analysis tool. Overnight sleep studies were conducted on 20 healthy subjects during a validation clinical trial which compared the NAPS system to actigraphy, using polysomnography as the gold standard. The NAPS system [κ = 3D 0.478; 95% CI (0.463, 0.494); p-value < 0.001] outperformed actigraphy [κ = 3D 0.344; 95% CI (0.324, 0.358); p-value < 0.001], largely due to better performance in distinguishing sleep onset times as determined by polysomnography [NAPS mean bias estimate: -2.5 epochs; 95% CI (-16.8, 11.9); p = 3D 0.725 | Actigraphy mean bias estimate: -33.6 epochs; 95% CI (-57.4, -9.7); p = 3D 0.016)].

The National Institutes of Health (NIH) Sleep Disorders Research Plan expresses a need for methods that can non-invasively monitor sleep characteristics. Forty subjects were tested using a novel, passive ballistocardiography-based system during an overnight study. We examined our system's ability to measure heart rate as compared to EKG while we also investigated our system's apnea and arousal detection capabilities as compared to conventional polysomnography. We found a strong correlation (r=0.972, p