Can a diagnosis of Asperger syndrome be made in very young children with suspected autism spectrum disorder?

Of a cohort of 104 children with Autism, PDD-NOS or specific language disorder, recruited at age 2-3 years of age, only three appeared to meet diagnostic assessment criteria for Asperger syndrome (AS). The children were followed up at 4-5 years, and assessments at both time points included the Autism Diagnostic Interview (ADI-R), the Autism Diagnostic Observation Schedule (ADOS) and the Mullen Scales of Early Learning. The paper explores the reasons why so few children with possible AS were identified early, including problems inherent in the assessment tools and the range of normal variation within characteristics required for a diagnosis. Only 10 children altogether had first words by 24 months, and abilities in the average range, and 9 were followed up. All of these able children had varied repetitive behaviours, and these increased in terms of ADI-R algorithm score over a 13 month interval. However, items concerning resistance to change and liking of routines tended to decrease in terms of reported impact on the child and family. Repetitive behaviours seem significant in the early referral of able children for a PDD diagnosis, but identification of children with AS is more likely to occur reliably once children are older and enter school.