Table 3.

Correlation between PSQI scores and patients’ demographic and clinical characteristics.

PSQI components	Age	Gender	Marital status	Education level	BMI	Stage
Sleep quality	−0.054	0.053	0.006	−0.028	−0.170	0.192
Sleep latency	0.061	−0.050	0.058	−0.153	−0.072	0.174
Sleep duration	0.129	−0.209*	0.070	−0.133	0.044	0.140
Sleep efficiency	0.218*	−0.172	−0.004	−0.283**	−0.132	0.256**
Sleep disturbance	0.242*	0.015	−0.066	−0.211*	−0.082	0.153
Use of sleep medication	−0.002	−0.031	0.052	−0.057	−0.051	0.198*
Daytime dysfunction	−0.059	−0.029	0.096	0.219*	−0.179	0.145
PSQI global score	0.121	−0.91	0.048	−0.168	−0.174	0.234*

Abbreviation: PSQI, Pittsburgh Sleep Quality Index; *P < 0.05; **P < 0.01.