Table 2. Logistic regression for daily Internet usage on mental health.

		Subjective health status	Stress	Feeling of sadness	Suicidal ideation
Model 1b Internet usage time	Above average usage	1	1	1	1
	Below average usage	0.63 (0.59–0.67)	0.81 (0.75–0.88)	0.88 (0.82–0.93)	0.74 (0.68–0.80)
	p-valuea	< .001	< .001	< .001	< .001
Model 2c Internet usage time	Above average usage	1	1	1	1
	Below average usage	0.67 (0.63–0.71)	0.83 (0.76–0.90)	0.90 (0.84–0.96)	0.75 (0.69–0.82)
	p-value*	< .001	< .001	< .001	< .001

^ap-value of Likelihood Ratio test.

^bModel 1: Adjusted for grade level and sex.

^cModel 2: Adjusted for grade level, sex, academic achievement, living arrangement, economic status, and type of school.