Table 3.

Results from the moderated regression analysis predicting depressive symptoms in baseline and 1 year later

	Predictors	Model 1				Model 2
		β	t	ΔR2	F	β	t	ΔR2	F
Cross-sectional effect
1	PMPU	0.368	9.042**	<0.001	0.009	0.375	8.982**	0.001	0.238
	IFG-OcG	2.377	1.336			1.445	0.783
	PMPU × IFG-OcG	0.020	0.096			0.103	0.488
2	PMPU	0.368	9.064**	0.004	1.216	0.376	9.003**	0.007	2.316
	OrG-OcG	2.860	1.531			2.018	1.057
	PMPU × OrG-OcG	0.260	1.103			0.365	1.523
3	PMPU	0.352	8.756**	0.021	7.038*	0.351	8.527**	0.028	9.304**
	PhG-MTG	2.663	1.757			2.167	1.430
	PMPU × PhG-MTG	0.477	2.653*			0.554	3.050**
Longitudinal effect
1	PMPU	0.172	4.104**	0.002	0.584	0.173	3.979**	0.002	0.531
	IFG-OcG	−2.014	−1.101			−1.663	−0.862
	PMPU × IFG-OcG	0.164	0.764			0.161	0.729
2	PMPU	0.168	4.006**	0.001	0.239	0.172	3.923**	0.001	0.219
	OrG-OcG	−0.588	−0.304			−0.713	−0.352
	PMPU × OrG-OcG	0.119	0.489			0.118	0.468
3	PMPU	0.147	3.526**	0.026	6.754*	0.149	3.412**	0.023	5.847*
	PhG-MTG	0.559	0.356			0.587	0.366
	PMPU × PhG-MTG	0.484	2.600*			0.463	2.418*

Note: *P < 0.05, **P < 0.01, model 1 was did not adjust any variables, model 2 was adjusted by age, gender, residential area, any siblings, perceived family income and parents' education level. PMPU, problematic mobile phone use; IFG, inferior frontal gyrus; OcG, occipital gyrus; OrG, orbital gyrus; PhG, parahippocampal gyrus; MTG, middle temporal gyrus.