The seven deadly sins: measuring overvaluation of social media with the Plannet 25 scale Ciudad-Fernández, Víctor Zarco-Alpuente, Alfredo Escrivá-Martínez, Tamara Gomis-Vicent, Elena Espejo, Begoña Leucona, Óscar Perales López, José César Lopez-Fernandez, Olatz Baños, Rosa Problematic social media use Validation Psychometrics properties Background: Problematic social media use refers to the excessive and maladaptive use of social media platforms, which negatively affects personal, social, and professional functioning. Although linked to mental health issues such as depression, anxiety, and loneliness, the underlying mechanisms remain unclear. A potential contributing factor to Problematic Social Media Use (PSMU) is the overvaluation of the relative utility of social media, where individuals disproportionately overvalue social media for different utility domains (e.g., communication or emotional regulation). This study aimed to develop and validate the Plan-net 25 scale, which was designed to assess overvaluation of the relative utility of social media in adolescents. Methods: The study followed three phases. Initially, a Delphi panel of 14 experts evaluated items across different utility domains. A pilot study involving 17 adolescents was conducted, and cognitive interviews were subsequently used to refine the scale items. Finally, the scale was administered to a large sample of 2,477 adolescents aged 12–20 years in Spain, alongside assessments of depression, anxiety, loneliness, life satisfaction, self-esteem, and problematic social media use. The analyses included confirmatory factor analysis, Pearson correlation, and network analysis, all of which were conducted via R 4.3.2. Results: Confirmatory factor analysis supported the theoretical seven-factor structure, capturing the following overvaluation of the relative utility of social media domains: social interaction, meeting new people, emotional regulation, social acceptance, staying informed, self-expression, and boredom management. The scale demonstrated full measurement invariance across gender and age groups (early and late adolescence). Significant correlations were found between overvaluation of the relative utility of social media, problematic social media use, and mental health indicators, with the emotional regulation and entertainment overvaluation of the relative utility of social media domains showing the strongest associations with problematic social media use. Conclusions: The Plan-net-25 scale exhibited robust psychometric properties, suggesting that it is a promising tool for assessing overvaluation of the relative utility of social media during adolescence. 2025-12-05T10:00:12Z 2025-12-05T10:00:12Z 2025-05-27 journal article Ciudad-Fernández, V., Zarco-Alpuente, A., Escrivá-Martínez, T. et al. The seven deadly sins: measuring overvaluation of social media with the Plan-net 25 scale. BMC Psychol 13, 569 (2025). https://doi.org/10.1186/s40359-025-02801-1 https://hdl.handle.net/10481/108611 10.1186/s40359-025-02801-1 eng http://creativecommons.org/licenses/by/4.0/ open access Atribución 4.0 Internacional Springer Nature