Depression fully mediates the effects of problematic internet use on nonsuicidal self-injury among adolescents during the COVID-19 outbreak.

The outbreak of the coronavirus disease 2019 (COVID-19) pandemic threatened adolescents' mental health and livelihoods, which can worsen their non-suicidal self-injury (NSSI) behaviors. With the significant increase of total online time use, adolescents become more prone to problematic internet use (PIU). This study examined whether depression mediated the relationship between PIU and NSSI among adolescence during the COVID-19 outbreak. Constructed with a cross-sectional design during the COVID-19 outbreak in Taiwan, 1060 participants were drawn from junior high schools through stratified and cluster sampling, and completed a set of comprehensive surveys. The mediation model demonstrated a good fit to the data, GFI = .96, CFI = .97, NFI = .97, NNFI = .95, IFI = .97, and SRMR = .02. The overall fit of the mediational model was adequate. The path from PIU to depression, β = .41, p < .001, and the path from depression to NSSI, β = .40, p < .001, were both significant. Moreover, the effect of PIU to NSSI decreased from .23 (p < .001) to .05 (p = .099) when depression was incorporated into the analysis. Moreover, results in bootstrapping analysis displayed that the indirect effect (PIU on NSSI via depression) was statistically significant (p < .001) and the direct effect (PIU on NSSI) was statistically non-significant (p = .134). The full mediation model was confirmed. The findings of the structure equation modeling and bootstrap analysis showed that PIU significantly and positively predicted NSSI, and that depression fully mediated this relationship.