Differences between, on the one hand, North American and European perspectives on Hyperkinetic Disorder, and, on the other hand, within Europe are noted and discussed in this paper. A dominant European tradition has stressed, since the beginning of this century, the organic involvement in hyperkinetic disorder, whereas the North American tradition has stressed both behavioural and social functioning in hyperactivity (Attention Deficit Hyperactivity Disorder) and its associated disorder, Conduct Disorder. Five reasons for the difference in prevalence between the two perspectives are discussed: association disorder, decision rules, expression of behaviour, weighting of symptoms, and diagnostic instruments. The review suggests that the differences within Europe in the diagnosis, management, and treatment should be utilized in well-designed collaborative studies to investigate the validity of the different diagnostic and therapeutic procedures. The coordination of such studies is seen as the main task of the newly founded European Network on Hyperkinetic Disorder (EUNETHYDIS).
Keywords: Attention Deficit Hyperactivity Disorder; Collaborative Study; Decision Rule; Organic Involvement; Therapeutic Procedure.