Overlap of ADHD and oppositional defiant disorder DSM-IV derived criteria.

Objective: One possible reason for being controversies regarding ADHD may be related to the validity and reliability of diagnostic criteria of attention deficit hyperactivity disorder and oppositional defiant disorder. Diagnostic criteria of oppositional defiant disorder include eight symptoms. This study examines the factor structure of oppositional defiant disorder symptoms, its discriminant validity from attention deficit hyperactivity disorder, its convergent validity and internal reliability.

Methods: Parents of 111 referral children and adolescents with attention deficit hyperactivity disorder completed DSM-IV referenced based attention deficit hyperactivity disorder and oppositional defiant disorder checklists.

Results: Factor analysis indicated that the attention deficit hyperactivity disorder symptom of: "often has trouble organizing activities" and "often runs about or climbs when and where it is not appropriate" were a part of the oppositional defiant disorder component. These symptoms less often than other symptoms differentiate attention deficit hyperactivity disorder from oppositional defiant disorder. The convergent validity for oppositional defiant disorder symptoms ranged from 0.64 to 0.79.

Conclusion: The parent-rating checklist of oppositional defiant disorder symptoms properly differentiates oppositional defiant disorder from attention deficit hyperactivity disorder. However, two items of the attention deficit hyperactivity disorder were listed as symptoms of oppositional defiant disorder. If the factor loading of the items is to be confirmed in further studies, it might be necessary to revise these symptoms criterion in future editions of DSM-IV diagnostic criteria.