BackgroundIncreased smartphone use by children and adolescents places them at higher risk of overdependence. The problematic smartphone use of preteens is rapidly increasing. The preteen period is one of considerable developmental change and the influence of problematic smartphone use should be identified by reflecting on this change and considering its social psychological factors.MethodsThis study employed a secondary analysis using data from the 10th (2017) to 11th (2018) wave of the Panel Study on Korean Children. STATA/BE 17 was used to analyze the panel logit model. Among the 1,286 participants aged 9–10 from the Panel Study on Korean Children, 342 with complete responses were selected as the participants of this study.ResultsThe risk group for problematic smartphone use showed an increase from 126 in 2017 to 149 in 2018. Factors influencing risk of preteens' problematic smartphone use were the child's externalizing problems (p = 0.015) and permissive parenting behavior (p = 0.003). Protective factors influencing preteens' problematic smartphone use were peer communication (p = 0.023), parental supervision (p = 0.020), and authoritative parenting behavior (p = 0.001).ConclusionsPreteens with externalizing problems are at a higher risk for problematic smartphone use and are therefore a group to be observed with caution. It is also required to guide them to form good relationships with friends. Finally, in the problematic smartphone use of preteens, parents are both a protective factor and a risk factor. Therefore, guidance is required so that children can behave properly.

Background: In the socially distanced era triggered by the coronavirus disease 2019 pandemic, there has been a surge in online activities across children’s and adolescents’ lives. Increased smartphone use by children and adolescents places them at higher risk of overdependence. Methods: The purpose of this study, using secondary data from the 10th to 11th wave of the Panel Study on Korean Children, was to longitudinally investigate problematic smartphone use in preteens and to comprehensively understand the effects of variability and diversity in preteen development on excessive smartphone use. STATA/BE 17 was used to analyze the panel logit model. Among the 1,286 participants aged 9–10 from the Panel Study on Korean Children, 342 with complete responses (from the parent, child, and school teacher) were selected as the subjects of this study. Results: The size of the risk group for preteens’ problematic smartphone use showed a trend of increasing from 126 in 2017 to 149 in 2018. Factors influencing smartphone overdependence included the authoritative parenting behavior, permissive parenting behavior, child’s externalizing problems, peer communication, and parental supervision. Factors related to parents and peers, as well as their own characteristics, had a complex effect on preteens’ problematic smartphone use. Conclusions: To reduce preteens’ smartphone overuse, it is necessary to avoid permissive parenting behaviors and to increase parental monitoring of this population. Interventions should be conducted that focus on reinforcing parenting behaviors that respect preteen’s opinions and set rules together, and strengthen preteen’s communication with their peers.