Temperament Profiles Associated with Internalizing Symptoms and Externalizing Behavior in Adolescents with ADHD

The current study investigated temperament profiles associated with internalizing symptoms and externalizing behavior in adolescents with ADHD. Participants were 121 adolescents (90 males) with ADHD, ranging in age from 13 to 18 years (M = 15.40, SD = 1.59). Emotional and behavioral ratings were obtained using the Strengths and Difficulties Questionnaire (SDQ) and temperament profiles were assessed by administering the Temperament and Character Inventory (TCI). Multivariate profile analyses and post hoc tests revealed that youth high in internalizing symptoms were significantly higher in harm avoidance and lower in self-directedness. Youth high in externalizing behavior were significantly lower in cooperativeness. No cognitive differences were observed across groups, but youth high in externalizing behavior had more ADHD symptoms and greater impairment in daily life. Findings reveal unique temperament factors associated with comorbid concerns, which may have implications for adapting and personalizing intervention efforts based on these different profiles within adolescents with ADHD.