Factor loadings of the SMDS-P items on single factor and correlations with external criteria. Notes: Significant EFA SMDS-P item factor loadings are presented on the left side. Correlation coefficients with variables used to ascertain criterion validity are presented on the right side. All correlations were significant based on their p values with *** p ≤ 0.001, ** p ≤ 0.01, and * p ≤ 0.05. EFA = explanatory factor analysis, SMDS-P = Social Media Disorder Scale-Parental Version, SMDS = Social Media Disorder Scale, usage days = weekly usage frequency, usage time = average usage time per day, DERS-SF = Difficulties in Emotion Regulation Scale—Short Form, grades sum = summed grade score of the three main subjects, with higher scores indicating poorer academic performance, Absence = absence from school/work in the last three months, grades development = Change in the grade sum score in comparison with the last school report, with higher values indicating greater improvement.