Research Abstract |
The first purpose of this research is to investigate the age effect on sleep-wake rhythm. Morningness-Eveningness Questionnaire by Horne and Ostberg, and Life Habit Inventory were administered to 518 Japanese children (aged from 6 to 18), 1, 143 Japanese workers(aged from 18 to 65), and 1,098 Korean workers (aged from 19 to 58) The delay of the sleep phase, the reduction of sleep length, transition to Evening type, and the increased daytime napping were remarkably represented afler the second grade of jurior high school. In Japanese and Korean workers, the bedtimes were earlier and transition to the Morning type with increasing age. These results indicated the phase of sleep/wake rhythm had moved toward from the young to the aged. The second pirpose is to use the algorithms of Cole et al(1992) and Park and Matsumoto(1998) for identifying sleep/wakefulness periods and compare the resuls with those by a 78 night polysomnograph(PSG) to study the degree of agreement between the two methods The rete of agreement of the sleep/wakefulness periods identified by using both actigraph counts and PSG was 95.9% when the algorithm of Cole et al was used, and 96.5% when the algorithm of Park and Matsumoto was used. From the above results, it is suggested that an ambulatory activity monitor actigraph can identify sleep and wakefulness periods with certain accuracy It will be useful to explore its use in a variety of field studies
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