Table 3.

Multivariate logistic regression analysis of poor sleep quality.

	Beta	S.E.	p	OR	95% CI
Investigation year
2008				Ref.
2011	0.079	0.032	0.014	1.08	1.02–1.15
2014	0.248	0.038	<0.001	1.28	1.19–1.38
2018	0.660	0.030	<0.001	1.94	1.82–2.05
Gender
Male				Ref.
Female	0.328	0.032	<0.001	1.39	1.30–1.48
Marital status
Unmarried				Ref.
Married	0.182	0.108	0.092	1.20	0.97–1.48
Divorced or widowed	0.266	0.108	0.013	1.30	1.06–1.61
Category of residence
Rural				Ref.
Urban (city and town)	−0.060	0.025	0.016	0.94	0.90–0.99
Economic status
Rich				Ref.
General	0.177	0.034	<0.001	1.19	1.12–1.28
Poor	0.471	0.048	<0.001	1.60	1.46–1.76
Numbers of chronic diseases
0				Ref.
1	0.131	0.029	<0.001	1.14	1.08–1.21
≥2	0.417	0.029	<0.001	1.52	1.43–1.61
Smoking status
Never				Ref.
Previous	−0.019	0.040	0.630	0.98	0.91–1.06
Current	−0.173	0.034	<0.001	0.84	0.79–0.90
Regular exercise
Never				Ref.
Previous	0.191	0.045	<0.001	1.21	1.11–1.32
Current	0.010	0.027	0.725	1.01	0.96–1.06
Dietary diversity score
Poor				Ref.
Moderate	−0.246	0.027	<0.001	0.78	0.74–0.83
Good	−0.192	0.036	<0.001	0.83	0.77–0.88
Housework
Almost everyday				Ref.
Sometimes	0.110	0.035	0.002	1.12	1.04–1.20
Never	−0.031	0.034	0.363	0.97	0.91–1.04
Outdoor activities
Almost everyday				Ref.
Sometimes	0.185	0.027	<0.001	1.20	1.14–1.27
Never	0.004	0.035	0.913	1.00	0.94–1.08
Keeping pets or gardening
Almost everyday				Ref.
Sometimes	0.022	0.049	0.662	1.02	0.93–1.13
Never	0.115	0.032	<0.001	1.12	1.05–1.20
Reading books
Almost everyday				Ref.
Sometimes	−0.208	0.044	<0.001	0.81	0.74–0.89
Never	−0.075	0.039	0.054	0.93	0.86–1.00
Raising poultry
Almost everyday				Ref.
Sometimes	−0.029	0.048	0.550	0.97	0.88–1.07
Never	−0.095	0.028	0.001	0.91	0.86–0.96
Watching TV
Almost everyday				Ref.
Sometimes	0.131	0.032	<0.001	1.14	1.07–1.21
Never	0.196	0.037	<0.001	1.22	1.13–1.31
Social participation
Almost everyday				Ref.
Sometimes	0.354	0.067	<0.001	1.43	1.25–1.62
Never	0.274	0.064	<0.001	1.32	1.16–1.49
BMI
Normal				Ref.
Underweight	0.146	0.033	<0.001	1.16	1.08–1.24
Overweight	−0.206	0.030	<0.001	0.81	0.77–0.86
Obesity	−0.242	0.061	<0.001	0.79	0.70–0.89
Activities of daily living
Independent				Ref.
Disabled	−0.110	0.050	0.027	0.90	0.81–0.99
Self–reported quality of life
Good				Ref.
General	0.446	0.026	<0.001	1.56	1.48–1.64
Poor	0.604	0.060	<0.001	1.83	1.63–2.06
Self–reported health
Good				Ref.
General	0.800	0.026	<0.001	2.23	2.11–2.34
Poor	0.942	0.037	<0.001	2.56	2.39–2.75