Table 1.

Group comparisons between residents with MHP and residents without MHP.

Independent variables		MHP (N = 36)	No MHP (N = 172)	Main effect of group		Group-by-time interaction		Post-hoc test
		M (SD)	M (SD)	F(1, 206)	p	F	p	t	p
General Health Questionnaire-12, (GHQ)	T1	4.5 (4.4)	3.3 (4.1)	11.019	0.001*	1.161	0.282	1.554	0.122
	T2	4.2 (3.4)	2.0 (2.7)					4.233	<0.001**
Patient Health Questionnaire-9 (PHQ)	T1	3.2 (4.6)	1.8 (2.7)	16.749	<0.001**	5.338	0.022*	2.431	0.016*
	T2	3.4 (5.2)	1.0 (1.9)					4.826	<0.001**
Rosenberg Self-Esteem Scale (RSES)	T1	24.9 (4.5)	26.6 (4.3)	12.943	<0.001**	6.323	0.013*	−2.219	0.028*
	T2	23.5 (4.6)	27.1 (4.7)					−4.205	<0.001**
GPIUS2 Total score	T1	41.6 (19.5)	36.0 (16.0)	4.017	0.046*	0.023	0.880	1.838	0.067
	T2	42.0 (20.9)	37.0 (16.8)					1.569	0.118
GPIUS2 Preference for online social interaction	T1T2	7.9 (4.5) 8.2 (4.8)	6.4 (3.6) 6.9 (4.0)	5.159	0.024*	0.75	0.785	2.078 1.658	0.039* 0.099
GPIUS2 Mood regulation	T1	9.4 (4.7)	9.4 (4.7)	1.766	0.185	3.764	0.054	0.043	0.966
	T2	9.8 (5.4)	8.1 (4.5)					2.008	0.046*
GPIUS2 Deficient self-regulation	T1	16.6 (8.0)	14.6 (7.0)	1.563	0.213	0.497	0.481	1.512	0.132
	T2	17.1 (10.1)	16.3 (7.8)					0.515	0.607
GPIUS2 Negative outcomes	T1	7.0 (4.7)	5.6 (3.6)	0.803	0.371	3.42	0.066	1.999	0.047*
	T2	7.4 (5.6)	7.7 (4.5)					−0.377	0.707

MHP, mental health problems; GPIUS2, Generalized Problematic Internet Use Scale 2; SD, standard deviation; T1, Time 1 (baseline); T2, Time 2 (3 months after baseline),

^*p < 0.05,

^**p < 0.01.