Epidemiology of autistic disorder and other pervasive developmental disorders.

TLDR

Recent epidemiological surveys have increased awareness of autistic disorder and other pervasive developmental disorders, but methodological differences over time hinder comparisons. The study investigates whether the incidence of autistic disorder and other PDDs is increasing. Prevalence estimates are influenced by assessment methods, sample size, publication year, and geographic location. Recent surveys estimate a prevalence of all PDDs at about 60 per 10,000, with autism at 13 per 10,000, Asperger's at 3 per 10,000, childhood disintegrative disorder at 0.2 per 10,000, and associations with IQ, gender, and other medical disorders.

Abstract

Is the incidence of autistic disorder and other pervasive developmental disorders (PDDs) increasing? Recent epidemiological surveys of autistic disorder and other PDDs have heightened awareness of and concern about the prevalence of these disorders; however, differences in survey methodology, particularly changes in case definition and case identification over time, have made comparisons between surveys difficult to perform and interpret. Recent surveys suggest that the rate of all PDDs is about 60 per 10,000. The prevalence of autism today is estimated at 13 per 10,000, Asperger's disorder is approximately 3 per 10,000, and childhood disintegrative disorder is very rare at about 0.2 per 10,000. The assessment process, sample size, publication year, and geographic location of studies all have an effect on prevalence estimates. In addition, data from many of these surveys indicate correlates of autistic disorder and other PDDs with IQ, gender, and other medical disorders.