The Relationship between Children's School Adaptation, Academic Achievement, Happiness, and Problematic Smartphone Usage: A Multiple Informant Moderated Mediating Model.

The school environment is a primary realm of life for school-aged children and thus their adaptation to school and academic performance may affect their degree of happiness. The age of smartphone users has declined, and problematic smartphone usage has widely expanded such that young children are also affected by such devices. This study assessed adaptation to school, academic achievement, problematic smartphone usage, and general happiness in a panel data sample of 695 Korean 10-year-old children and their teachers and mothers, and a moderated mediation model of these variables was tested. Results revealed that school adaptation affected general happiness of children through academic performance, and problematic smartphone usage demonstrated significant moderating effects on the relationship between school adaptation and academic achievement. Specifically, in children with a high level of adaptation to school life, the difference in problematic smartphone usage did not affect academic performance. However, lower level of adaptation led to greater differences in academic performance depending on problematic smartphone usage, and children with high problematic smartphone usage showed poorer academic performance. This study is meaningful because variables related to adaptation of 10-year-old children were collected from multiple informants. In addition, this study focused on general happiness, a positive factor, as the outcome variable to test the effects of variables related to school and problematic smartphone usage. Limitations include that a causal relationship cannot be examined, and qualitative differences in smartphone usage were not measured. Supplementary Information: The online version contains supplementary material available at 10.1007/s11482-022-10080-w.