Date of Award


Publication Type

Doctoral Thesis

Degree Name




First Advisor

Voelker, Sylvia,


Psychology, Clinical.




Examined the early history characteristics and symptom patterns of children with an initial diagnosis of either Pervasive Developmental Disorder, Not Otherwise Specified (PDD NOS) or Autistic Disorder, and identified predictors of changing functional ability. Participants were 59 children (48 male, 11 female) who were first assessed at 3 to 4 years of age, and re-assessed two years later (M = 26.00 months, SD = 12.43). Based on the results of the follow-up assessment three groups were identified: children with a stable diagnosis of PDD-NOS (Stable PDD-NOS), a stable diagnosis of autism (Stable Autism), and those whose diagnosis changed from PDD-NOS to autism (Change). Overall, the Stable PDD-NOS group demonstrated a significantly better outcome than the Stable Autism group in all areas examined, including early history characteristics, symptom severity, and measures of functional ability. In contrast, the performance of the Change group was more variable and suggested a relative decline over time (i.e., an increase in symptom severity and a decline in functional ability). In terms of early history, the Change group appeared to experience greater impairments and more atypical behaviors than did the Stable PDD-NOS group. Results suggest that early history characteristics and patterns of PDD symptoms are predictive of later outcome for children initially diagnosed with PDD-NOS. Implications for research and practice are discussed.Dept. of Psychology. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2004 .F74. Source: Dissertation Abstracts International, Volume: 65-07, Section: B, page: 3706. Adviser: Sylvia Voelker. Thesis (Ph.D.)--University of Windsor (Canada), 2004.