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A Prospective Study of Toddlers With ASD: Short-Term Diagnostic and Cognitive Outcomes
Speech-Language Pathology Faculty Publications
  • Katarzyna Chawarska
  • Ami Klin
  • Rhea Paul, Sacred Heart University
  • Suzanne Macari
  • Fred Volkmar
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Background: Despite recent increases in the number of toddlers referred for a differential diagnosis of autism spectrum disorders (ASD), knowledge of short-term stability of the early diagnosis as well as cognitive outcomes in this cohort is still limited.Method: Cognitive, social, and communication skills of 89 clinic-referred toddlers were assessed at the average age of 21.5 (SD = 4.9) months, and reassessed at 46.9 (SD = 7.7) months. Groups with stable and unstable diagnostic presentation were identified and compared on their profile of cognitive and social-communicative skills obtained at the time of initial diagnosis.Results: Stability of the ASD diagnosis was 100%; diagnosis of autism was stable in 74% of cases as compared to 83% and 81% in PDD-NOS and Non-ASD groups, respectively. Worsening of social disability symptoms resulting in autism diagnosis was noted in 17% of toddlers initially diagnosed with PDD-NOS and in 19% of toddlers with initial diagnosis of non-ASD disorder. However, marked improvement was noted in approximately 1/4 of children initially presenting with autism, warranting diagnostic reassignment to PDD-NOS at follow-up. An analysis of developmental skills profiles suggests particular relevance of the assessment of verbal and nonverbal communication skills to diagnostic differentiation between subtypes within ASD in the second year of life.Conclusions: Stability of ASD diagnosis in toddlers is high, though marked changes in severity of symptoms is to be expected in a minority of cases. Simultaneous consideration of cognitive, social, and communication skills profiles enhances accuracy of diagnostic classification and prediction of outcome.

Originally published:

Chawarska, Katarzyna, Klin, Ami, Paul, Rhea, Macari, Suzanne, Volkmar, Fred. "A Prospective Study of Toddlers with ASD: Short-Term Diagnostic and Cognitive Outcomes." Journal of Child Psychology and Psychiatry 50.10 (2009): 1235-1245.

Citation Information
Katarzyna Chawarska, Ami Klin, Rhea Paul, Suzanne Macari, et al.. "A Prospective Study of Toddlers With ASD: Short-Term Diagnostic and Cognitive Outcomes" (2009)
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