ADHD Symptoms Among Adolescents: Factor Structure Based on Mother and Adolescent Self-Ratings

Background: At present, there is little data on the factor structure of ADHD symptoms in adolescents, especially as they are organized in the International Classification of Diseases-10 (ICD-10) or the recently proposed ADHD S-1 bifactor model. This study aimed to analyze how mother and adolescent self-ratings of ADHD symptoms align with these models. Methods: This study utilized confirmatory factor analysis (CFA) on a group of 300 adolescents (ages ranging from 11 to 17 years) to examine the factor structure in terms of mother ratings and adolescent self-ratings of ADHD symptoms (inattention [IA], hyperactivity [HY], and impulsivity [IM]) presented in the Disruptive Behavior Rating Scale (DBRS). Based on existing theory, the study examined five structural ADHD models: (1) DSM-5/ICD-10 one-factor model (with all symptoms loading on a single factor); (2) DSM-5 two-factor model (with IA and HY/IM factors); (3) ICD- 10 three-factor model (with IA, HY, and IM factors); (4) DSM-5 bifactor S – 1 model (with HY/IM as the reference indicators for the general factor); and (5) ICD-10 bifactor S – 1 model (with IM as the reference indicators for the general factor). Additionally, mothers and adolescents completed the five-item hyperactivity scale in the Strengths and Difficulties Questionnaire (SDQ). Results: The results showed the most support for the ICD-10 three-factor model, with all three factors in this model showing adequate discriminant validity, good omega coefficient reliability values, and significant and positive association with SDQ hyperactivity. Furthermore, it is speculated that the ADHD structure in adolescents might involve a general ADHD factor alongside an IA-specific factor, omitting an HY component. Since the general factor was marked by the IM symptoms, this suggests that ADHD at a latent level could be typified by IA and IM symptoms, excluding HY symptoms. Conclusion: The theoretical implications of the findings are discussed.