NIGHTCAP MEASUREMENT OF SLEEP QUALITY IN SELF-DESCRIBED GOOD AND POORSLEEPERS

The Nightcap is a home-based sleep monitoring device that reliably dif ferentiates rapid eye movement sleep, nonrapid eye movement sleep and wake states using eyelid and body movement measurements. This study do cuments its capacity to measure differences in sleep latency and sleep efficiency between self-described good and poor sleepers drawn from a normal population. Ten self-described ''good'' sleepers and 11 self-d escribed ''poor'' sleepers were selected from a pool of college studen ts. These groups differed significantly on selection parameters and on subjective estimates of sleep quality obtained each morning during th e study. Each subject wore the Nightcap at home for 12-17 nights. Stat istically significant differences in Nightcap-measured sleep latency a nd sleep efficiency were obtained between groups using individual subj ect means. In individual subjects, Nightcap measurements of sleep late ncy were correlated with subjective estimates of sleep latency. Poor s leepers were less accurate in estimating their sleep onset latency tha n were good sleepers. The demonstrated sensitivity of the Nightcap to good and poor sleep in these normal subjects augurs well for its appli cation in a clinical setting.