[Night sleep studies: mobile recording in comparison to conventional laboratory recording]

Night sleep registrations were made in a group of 11 persons in a laboratory using both traditional polygraphic methods and a portable home recording system. A significantly higher value in the evaluation of the sleep efficiency index (quotient of total sleep time and total time in bed) was found with the mobile recording system. Apart from these findings the latency to the beginning of the particular sleep stages (classification of Dement and Kleitman) were diminished. Furthermore there was found a significant decrease of stage 1 in favour of the REM-sleep. Regarding the relation between the REM and the NREM-time, a distinct difference could also be shown. As to the subjective sensitivity, 10 of the 11 tested persons preferred the mobile recording system.