Temporal directional relationship between problematic internet use and depressive symptoms among Japanese...

The results from research on the temporal directional relationship between problematic Internet use (PIU) and depressive symptoms are inconsistent. This study aimed to explore this relationship among junior high school students in Japan.

Junior high/middle school students in the seventh grade (Time 1, [T1]) were recruited annually for 4 years starting in 2014; each cohort was followed up at 1 year (Time 2, [T2]) and 2 years (Time 3, [T3]). Three-year longitudinal panel data were collected from self-reported questionnaires that were completed by 1192 students (586 males and 606 females). Young's Internet Addiction Test and the Birleson Depression Self-rating Scale were used to assess participants' PIU and depressive symptoms, respectively. The temporal directional relationship between PIU and depressive symptoms was analyzed using the random intercept, cross-lagged panel model.

The mean of the Internet Addiction Test increased as grade level increased: 28.0 at T1, 30.7 at T2 and 32.6 at T3. There was a unidirectional positive effect from PIU at T2 to depressive symptoms at T3, but not vice versa. There was no directional effect from PIU at T1 to depressive symptoms at T2, nor any in the reverse.

Our findings suggest that PIU precedes depressive symptoms. Therefore, addressing PIU is a promising preventive measure for adolescent depression.