Table 4. Regression coefficients of influence of parameters of sleep-wake cycle and sleep quality on BMI (N=147).

Variable		Unadjusted			Adjusted
		β	95% CI	p	β	95% CI	p
Age
	21–30 yr	Reference			Reference
	31–40 yr	0.09	−1.08 to 3.50	0.297	0.01	−2.59 to 2.90	0.913
Marital status
	Single	Reference			Reference
	Married	0.07	−1.82 to 4.68	0.387	0.13	−0.87 to 5.95	0.142
Educational background
	Junior college	Reference			Reference
	University or above	−0.12	−2.82 to 0.46	0.158	−0.12	−2.85 to 0.52	0.173
Years of service
	<2 yr	Reference			Reference
	2–5 yr	0.13	−0.56 to 3.41	0.159	0.1	−0.83 to 2.97	0.283
	>5 yr	0.14	−0.56 to 3.47	0.142	0.22	0.01 to 4.71	0.049
Shift type
	Day	Reference			Reference
	Evening	0.1	−0.86 to 2.90	0.286	0.14	−0.31 to 3.36	0.103
	Night	−0.01	−2.14 to 2.90	0.98	−0.15	−3.86 to 0.41	0.112
I<O		−0.28	−2.06 to 0.58	0.001	−0.24	−1.94 to 0.32	0.007
PSQI score		0.27	0.18 to 0.70	0.001	0.2	0.06 to 0.59	0.016

β: standardized regression coefficient; CI: confidence interval; I<O: dichotomy index; PSQI: Pittsburgh Sleep Quality Index.