Social media use disorder (SMUD) is associated with substantial impairments in daily functioning, and adolescents are particularly at risk. The 11th revision of the International Classification of Diseases (ICD-11) criteria of gaming disorder (GD) could be shown to be suitable to describe SMUD in adolescents. Since adolescents' insight might be limited due to young age or symptom denial, it is essential to include their parents in the diagnostic process. The development and validation of a parental scale are, therefore, of great interest to clinicians and scientists. The Social Media Use Disorder Scale for Parents (SOMEDIS-P) was developed by clinical experts and validated in 944 parent–child dyads. Adolescents were 10–17 years old and frequently used social media (SM). Besides SM use times, standardized questionnaires were applied to assess SM use patterns according to ICD-11 and Diagnostic and Statistical Manual of Mental Disorders-5 criteria of (Internet) GD, psychological stress, and depressive symptoms in an online survey. Item structure was investigated by confirmatory factorial analysis. Receiver operating characteristic curve analyses to determine cutoff values and accordance with adolescent self-ratings were computed. A presumed two-factorial structure of SOMEDIS-P could be confirmed describing cognitive-behavioral symptoms and negative consequences. The instrument showed good to excellent internal consistency and criterion validity with moderate to strong correlations, excellent discriminatory characteristics, and moderate accordance with the adolescents' self-ratings. As the first successfully validated tool for the assessment of ICD-11-based SMUD in adolescents by parental judgment, SOMEDIS-P can make an important contribution to reliable SMUD screening in clinical practice and research.
