Department of Child Health, University of Missouri-Columbia.
To assess change in autism prevalence in Missouri from 1988 until 1995, computerized client registries from the Regional Diagnostic Centers were analyzed. In the five to nine year age group, the prevalence rose thirty fold from 0.15 to 4.8 per 10,000. The study period coincides with the establishment of the Missouri Autism Project suggesting that provision of services will increase the apparent prevalence figures and that autistic disorders were previously underdiagnosed in Missouri.