Unraveling problematic smartphone use The good and the bad through longitudinal, qualitative and psychometric perspectives

In an era where smartphones have become ubiquitous, discerning the fine line between normal smartphone use and Problematic Smartphone Use (PSU) is critical. This dissertation investigates the dual nature of smartphone use, delineating its positive and negative consequences, defining PSU comprehensively, and exploring its etiology through a mixed-methods approach. This approach involves a longitudinal study, an in-depth qualitative exploration, and the development of the Smartphone Use Problems Identification Questionnaire (SUPIQ). Chapter 2 presents findings from a longitudinal study with 2100 Dutch high school students, examining the bidirectional relationship between PSU and adolescent peer engagement. The study identifies individuals with low perceived competence in close friendships and those who intensively engage with smartphones for peer communication as particularly vulnerable to PSU. Chapter 3 offers a qualitative exploration of PSU symptoms and possible etiology, finding the similarities and differences between PSU and established addiction criteria and highlighting the trade-off process between smartphones’ positive and negative consequences. Building on these insights, Chapter 4 details the development and validation of the SUPIQ through the analysis of two distinct samples. The SUPIQ demonstrated strong construct validity and superior predictive power for mental health problems. This thesis illuminates the intricate interplay of social, motivational, and normative factors in PSU, enriching the discourse on digital well-being. We argue for interventions that promote digital well-being through a balanced approach to smartphone use rather than advocating for its elimination, offering valuable perspectives on navigating the complexities of smartphone integration into daily life.