The purpose of this study was to investigate the relationships among circadian sleep types, quality of sleep, and adaption to night shifts among nurses working on two or three day night duties..
The subjects were 199 ward nurses that worked on two or three day night duties one time and average six to seven days per month frome G University Hospital in J City and S University Hospital in C City.
As for research instruments, the circadian sleep types was measured whit Self-Assessment Questionnaire to Determine Morningness-Evenin-
gness developed Horne and ?stberg (1976) and translated, revised, and supplemented to fit the situations of South Korea by Im Nan-yeong (1985) for circadian sleep types. The quality of sleep was measured with Verran & Synder-Halpern (VSH) Sleep Scale developed by Verran and Synder (1987), translated by Kim Gyeong-hee (2001), and revised and supplemented by Yun Seon-hee (2008). Adaptation to night shifts was measured with Scale of Adaptation to Night Shifts developed by Kim Hye-jeong (1987) and revised and supplemented by Kim Ok-ju (2000).
Data were analysed using descriptive statics t-test, ANOVA, Scheffe-test, and Pearson''s correlation coefficient with the SPSS/WIN 14.0 program.
The research findings were summarized as follows:
1. As for the numbers of nurses circadian sleep types, there were 38(19.1%) on morningness type, 119(59.8%) on middle type, and 42(21.1%) on eveningness type.
2. The mean that were scores of quality of sleep were 4.92±1.46 on a 5point scale. In subdimonsions, they were 4.40±2.42 on waking up during sleep, 4.84±2.16 on tossing and turning, 5.90±1.99 on total hours of sleep, 5.14±2.09 on soundness of sleep, 5.46±3.27 on time to take to go to sleep, 3.76±2.00 on how one feels when waking up, 5.16±2.02 on how one wakes up, and 4.68±1.76 on satisfaction with sleep.
3. There were 2.66±.47 on a 5point scale on adaptation to night shifts. In subdimonsions, 2.89±.61 on job performance, 2.91±064 on sleep and resting, 2.22±.55 on physical and mental health, 3.03±.71 on autonomy, 3.15±.50 on interpersonal relationships, and 2.41±.73 on attitude.
4. There were differences in quality of sleep according to the status of health (F=10.986, p=.000), hours of sleep on the days of night shifts (t=-3.339, p=.001), differences in hours of sleep among day, evening, and night shifts (F=3.247, p=.023), and preference for night shifts (F=2.782, p=.042).
5. There were differences in adaptation to night shifts according to the status of health (F=5.536, p=.005), preference for night shifts (F=31.317, p=.000), and difficulty with night shifts last month (F=55.5122, p=.000).
6.There were no significant differences in quality of sleep according to the circadian sleep types of nurses.
7. There were no significant differences in adaptation to night shifts according to the circadian sleep types of nurses.
8. The analysis results of correlations between quality of sleep and adaptation to night shifts reveal that there were positive correlations between them (r=.246).
In conclusion, nurses working on two or three day night duties had low level of quality of sleep and adaptation to night shifts. Quality of sleep was in positive correlation with adaptation to night shifts. Therefore, it is necessary to improve the quality of sleep for adaptation to night shifts of nurse. More studies is needed to investigate the relationships among circadian sleep type, quality of sleep and adaptation to night shifts of nurses working on night duties.