Symptom profiles in children with ADHD: Effects of comorbidity and gender

Objective: To examine ratings and objective measures of attention-deficit/h yperactivity disorder (ADHD) symptoms to assess whether ADHD children with and without comorbid conditions have equally high levels of core symptoms a nd whether symptom profiles differ as a function of comorbidity and gender. Method: Four hundred ninety-eight children from the NIMH Collaborative Mul tisite Multimodal Treatment Study of Children With Attention-Deficit/Hypera ctivity Disorder (MTA) were divided into comorbid groups based on the paren t Diagnostic Interview Schedule for Children and assessed via parents' and teachers' Swanson, Nolan, and Pelham (SNAP) ratings and a continuous perfor mance test (CPT). Comorbidity and gender effects were examined using analys es of covariance controlled for age and site. Results: CPT inattention, imp ulsivity, and dyscontrol errors were high in all ADHD groups. Children with ADHD + oppositional defiant Or conduct disorder were rated as more impulsi ve than inattentive, while children with ADHD + anxiety disorders (ANX) wer e relatively more inattentive than impulsive. Girls were less impaired than boys on most ratings and several CPT indices, particularly impulsivity, an d girls with ADHD + ANX made fewer CPT impulsivity errors than girls with A DHD-only. Conclusions: Children with ADHD have high levels of core symptoms as measured by rating scales and CPT, irrespective of comorbidity. However , there are important differences in symptomatology as a function of comorb idity and gender.