Debate and argument: is autism a pervasive developmental disorder?

Autism in most diagnostic systems is classified among the developmental disorders. This is appropriate in almost all cases, even though the occasional appearance of fullblown autistic syndromes in adolescents (Gillberg, 1986) (and even adults; Gillberg, 1991) highlights the need to keep an open mind about the biological basis for autistic symptoms being a priori linked with developmental processes. Much less appropriate is the word "pervasive" which was introduced in the late 1970s as a compulsory prefix to "developmental disorder" when referring to autism and autistic-like conditions. "Pervasive developmental disorders" or "PDD" (of which autism constitutes a subclass) is the cover-all blanket term for lowand high-functioning cases meeting all or several of the criteria for autism (APA, 1980, 1987; WHO, 1990). However defined, autism in itself is not necessarily "pervasive". The pervasiveness may be said to be present in cases with autism and associated moderate, severe or profound mental retardation. However, even in such cases, the diagnosis of autism is separated from that of mental retardation in that autism is not as pervasive in all fields. In some cases with mild mental retardation, near average, average or above average intelligence, autism and autistic-like conditions, far from being pervasive, constitute disorders in which there may be specific deficits in social/cognitive functioning but with several areas left unscathed. Most authorities in the field of autism seem to agree that there are high-functioning and even "mild" cases. Is it not a contradiction in terms to make a diagnosis of "mild pervasive developmental disorder"? In the draft version of the IGD-10 {International Classification of Diseases; W H O , 1990), Asperger('s) syndrome is listed as a pervasive developmental disorder. Neither the cases described by Asperger (1944), nor many of those reported by Wing (1981), Gillberg (1989), or Szatmari, Brenner and Nagy (1989), could reasonably be described as "pervasively" impaired. How can anybody with clinical common sense tell these high-functioning individuals—and their relatives—that they have a "pervasive developmental disorder'' ? At the other extreme, we have to deal with the semantic confusion that stems from not including severe and profound mental retardation among "pervasive" developmental disorders. Neither the DSM-III-R {Diagnostic and Statistical Manual of Mental Disorders, 3rd edition, revised; APA, 1987), nor the latest draft version of the ICD-10 (WHO, 1990), classify these handicapping conditions as coming within the PDD category. Of the developmental disorders they undoubtedly are the most pervasive of all. Perhaps most disconcerting of all is the fact that many people currently labelled as suffering from PDD rather than from autism or an autistic-like condition are deprived of their lawful "autism rights". Laymen in the field are often those who