Table 2.

Factors associated with mental health

	Depressive symptoms			Anxiety			Suicidal ideation
	OR	95% CI	p-value	OR	95% CI	p-value	OR	95% CI	p-value
Sleep duration
≥8 h	Ref			Ref			Ref
≥6 h and <8 h	1.11	1.03–1.19	0.006	1.15	1.03–1.28	0.012	1.04	0.94–1.15	0.491
<6 h	1.30	1.20–1.41	<0.001	1.36	1.21–1.53	<0.001	1.24	1.11–1.38	<0.001
Sleep satisfaction
Sufficient	Ref			Ref			Ref
Just enough	1.41	1.32–1.50	<0.001	1.59	1.44–1.76	<0.001	1.52	1.39–1.67	<0.001
Not enough	2.20	2.06–2.34	<0.001	2.96	2.69–3.26	<0.001	2.18	1.99–2.39	<0.001
Sex
Male	Ref			Ref			Ref
Female	1.63	1.55–1.70	<0.001	1.72	1.62–1.84	<0.001	1.68	1.58–1.79	<0.001
School
Middle school (7–9)	Ref			Ref			Ref
High school (10–12)	0.91	0.87–0.96	0.004	0.87	0.81–0.93	<0.001	0.74	0.69–0.80	<0.001
Residential Area
Metropolitan	Ref			Ref			Ref
Urban	1.06	1.01–1.11	0.012	1.12	1.05–1.19	0.001	1.05	0.98–1.12	0.141
Rural	1.01	0.91–1.11	0.913	1.14	1.01–1.30	0.042	1.04	0.91–1.18	0.589
Subjective household economic status
High	Ref			Ref			Ref
Middle	0.91	0.87–0.96	<0.001	0.94	0.87–1.01	0.069	0.96	0.89–1.03	0.244
Low	1.31	1.22–1.40	<0.001	1.47	1.34–1.61	<0.001	1.65	1.51–1.81	<0.001
Co-residence with parents
Yes	Ref			Ref			Ref
No	1.18	1.07–1.30	0.002	1.04	0.91–1.20	0.568	1.31	1.15–1.50	<0.001
Subjective academic performance
High	Ref			Ref			Ref
Middle	1.08	1.02–1.14	0.008	0.95	0.88–1.03	0.238	0.95	0.87–1.03	0.179
Low	1.34	1.27–1.42	<0.001	1.24	1.15–1.33	<0.001	1.22	1.13–1.32	<0.001
Subjective health status
Good	Ref			Ref			Ref
Normal	1.45	1.38–1.53	<0.001	1.90	1.77–2.04	<0.001	1.61	1.50–1.73	<0.001
Bad	2.25	2.09–2.44	<0.001	3.88	3.54–4.24	<0.001	3.20	2.92–3.51	<0.001
Alcohol consumption
No	Ref			Ref			Ref
Yes	1.68	1.56–1.80	<0.001	1.40	1.27–1.55	<0.001	1.77	1.61–1.95	<0.001
Smoking status
No	Ref						Ref
Yes	1.62	1.45–1.80	<0.001	1.18	1.01–1.37	0.033	1.49	1.29–1.71	<0.001

OR, odds ratio; CI, confidence interval; Ref, reference