Psychosocial Characteristics of Children with Pervasive Developmental Disorders

The concept of pervasive development disorder (PDD) evolved from a recognition that there exists a continuum of autistic features and that some children may not have the breadth or severity of symptoms sufficient to justify a diagnosis of autism (Wing & Gould, 1979). Various labels were used in clinical practice, such as autistic-like and developmental delay with autistic features, but the vague nature of the diagnosis was unsatisfactory (Dahl, Cohen, & Provence, 1986). In the third edition of the Diagnostic and Statistical Manual of Mental Disorders (dsm-iii; American Psychiatric Association, 1980), these children were identified as atypical pdd and childhood-onset pdd and in dsm-iii-r (American Psychiatric Association, 1987), they were collected under the general term of pdd not otherwise specified (pdd-nos). Nonautism pdd was further separated by dsm-iv (American Psychiatric Association, 1994) and the tenth edition of the International Classification of Diseases and Related Health Problems (icd-10; World Health Organization, 1992) into Asperger disorder, Rett disorder, childhood disintegrative disorder (cdd), and pdd-nos. Common to all children with forms of pdd are core impairments in verbal and nonverbal communication skills and reciprocal social interactions and a pattern of repetitive and/or stereotyped behaviors and interests. These diagnostic groups are differentiated by the number and/or type of symptoms present and the natural history of these symptoms’ evolution over time. In particular, Rett disorder and cdd are strikingly dissimilar to classic autism. Each of these forms of nonautism pdd is worthy of separate discussion.