We examined how perceived parenting style, friendship satisfaction, and academic motivation influence the addictive use of smartphones longitudinally. We utilized the panel data (from 2010–2012) of Korean children and youth panel survey of the National Youth Policy Institute. Data were collected from 2,376 individuals in the first year (boys: 1,241, girls: 1,135), 2264 individuals in the second year (boys: 1,180, girls: 1,084), and 2,218 individuals in the third year (boys: 1,167, girls: 1,051). Results of the multivariate latent growth modeling indicated that higher democratic parenting (warmth, supervisory, and rational explanation) was related to lower addictive use of smartphones. And, the more perceived democratic parenting was high, the more academic motivation and friendship satisfaction were high. Also, friendship satisfaction and academic motivation negatively influenced the addictive use of smartphones; the more friendship satisfaction and academic motivation increased rapidly over time, the more the addictive use of smartphones decreased over time. These results imply that affective and supervisory parenting can positively impact peer relationship and learning motivation, and the satisfaction of peer relationship and academic motivation can be protective factors for the addictive use of smartphones.

Purpose: This study examines the moderating effect of gratitude on the mediating effect of deliberate rumination on the relationship between intrusive rumination and post-traumatic growth (PTG).Methods: We used self-report questionnaires to collect data from 450 18–68-year-old participants (M_age = 39.73, SD = 13.73) residing in major cities and regions across South Korea. Data that were collected from 411 participants were subjected to analysis. Version 25 of SPSS (Statistical Package for Social Science) and PROCESS macro were used to analyze mediation, moderation, and moderated mediation effects.Results: Deliberate rumination mediated the relationship between intrusive rumination and PTG. Gratitude moderated the effect of deliberate rumination on PTG. Finally, gratitude moderated the mediating effect of deliberate rumination on the relationship between intrusive rumination and PTG.Conclusion: Deliberate rumination and gratitude facilitate PTG for traumatized adults. In particular, gratitude reinforces the effect of deliberate rumination on PTG.

Objective There is limited understanding of which specific factors relate to smartphone addiction in the elderly. The aim of this study was to examine the relationship between types of smartphone use, digital literacy, and smartphone addiction in the elderly.Methods It used data from a survey on smartphone overdependence by the South Korea National Information Society Agency in 2019. Participants were 3,121 older people (1,627 males, 1,494 females; mean age=63.83 [standard deviation=2.88 years]). We conducted hierarchical multiple regression analysis.Results The results of a hierarchical multiple regression analysis indicated that smartphone usage time was positively related to smartphone addiction. Entertainment-seeking and life service types of smartphone use, and digital literacy were positively associated with smartphone addiction. Conversely, smartphone use for information-seeking and communication-seeking was negatively related to smartphone addiction.Conclusion This study suggests that it is necessary to understand different types of smartphone uses in the elderly and to educate the elderly on digital literacy to prevent smartphone addiction. In future studies, it will be necessary to re-confirm the relationship between smartphone usage type, digital literacy, and smartphone addiction in the elderly (including participants in their 70s or older).