Table 3.

General PSQI results and mean sleep time comparison by group

Variables	Group A	Group B	Group C	P-valuea
	N (%)b	N (%)	N (%)
Sleep quality				<0.001
Good	264 (61.3)	800 (52.0)	342 (40.2)
Poor	167 (38.7)	737 (48.0)	508 (59.8)
Mean PSQIc Score	5.32 ± 2.98	5.75 ± 2.95	6.63 ± 3.01
Mean sleep time(hour)	7.06 ± 1.58	6.63 ± 1.24	5.95 ± 1.47

^acomparison by chi-squared test

^bPercentage of subjects who reply above 3 at each PSQI questionnaire

^cPittsburgh Sleep Quality Index