Disorders of the autism spectrum.

摘要

In today's Lancet, Gillian Baird and colleagues1 report a prevalence of pervasive developmental disorders or autism spectrum disorders of 116-1 per 10000, much higher than previously thought. The researchers base these findings on a total population cohort of 56946 children aged 9-10 years in 12 districts in southeast Thames, UK, with ICD-10 criteria.For subtypes, the prevalence was 38-9 per 10 000 for childhood autism and 77- per 10 000 for other pervasive developmental disorders. Nearly 60% of pervasive developmentdisorders as a whole was atypical autism in accordance with recent UK and Swedish4 studies, which reported that about one half of pervasive developmental disorders was a not otherwise specified subtype, a DSM-IV equivalent of atypical autism.5 Baird and colleagues did not give the prevalence of the other three subtypes (ie, Rett's syndrome, childhood disintegrative disorder, and Asperger's syndrome), because they found no cases of the first two.