Attention-deficit/hyperactivity disorder (ADHD): validity of the subtypes

Already with the publication of the DSM-IV` the validity of the DSM-IV subtypes of ADHD was questioned. In addition, the ICD-10 describes different guidelines for subtype classification. Ever since the subtypes have been examined in many different ways. To gain further information about necessary alterations of the DSM-V the differences and points in common found in the subtypes are presented. Six different approaches are considered (behavioral, genetic, gender, developmental, neurobiological, and neuropsychological). The results suggest considering additional aspects beyond behavioral symptom criteria - especially neurobiological and neuropsychological criteria. Thereby a differentiation of the predominantly inattentive subtype is supported: into a) a subgroup with sluggish cognitive tempo, which possibly represents an independent disorder and b) a predominantly inattentive subtype of ADHD, but with slight symptoms of hyperactivity and impulsivity. Furthermore, some approaches imply an independent ADHD aggressive subtype or hyperkinetic conduct disorder. But up to the present the results are not univocal so that additional studies are required. It seems un,necessary to develop special criteria for boys and girls; but it must be taken into consideration more carefully that girls can also have ADHS. Finally, implications for future classification systems of ADHD and their relevance to different treatment approaches are discussed.