Age of recognition of pervasive developmental disorder.

In DSM-III, pervasive developmental disorder is divided into two major categories: infantile autism and childhood onset pervasive developmental disorder. The criteria differ, primarily, in the age of onset. The authors studied 129 patients who had received diagnoses of pervasive developmental disorder or a related disorder and found only five cases of apparent childhood onset pervasive developmental disorder. These five patients were behaviorally indistinguishable from those with other diagnoses. Practically, age of onset may be more appropriately termed "age of recognition," and its use as a major diagnostic criterion for such disorders may not be justified.