The highest autism prevalence ever?

Baron-Cohen et al. (2009) propose a world where there are 157/10,000 autistics. The authors used what they call a " novel approach " to autism epidemiology and this is worth a closer look.The study is based on questions sent to schools about the UK SEN (Special Education Needs) register, and a survey, including a screening questionaire, sent to parents of students aged 5 to 9 years. Many schools, 66 out of 162, refused to participate. Of schools that agreed, 79 of 96, representing 8824 out of 11,635 children, provided SEN register information. Of the surveys sent to parents, 29%, representing 3373 out of 11,700 children, were responded to.Participating schools located 83 children identified as autistic spectrum according to the SEN register. Of these, 10 children were assigned the specific diagnosis of autism (I ' ll call them " specific-autism " ), while the rest were assigned other autistic spectrum diagnoses ( " other-spectrum " ). None of these diagnoses was verified by Baron-Cohen et al. (2009) in any way. These 83 SEN children constitute 94/10,000 of the proposed 157/10,000.In the survey, parents were asked whether their child had an existing autistic spectrum diagnosis. The authors " confirmed, " to their standards, through information from parents only, diagnoses for 19 children. Four others attended special schools and were assumed to be " confirmed " as autistic without any verification, for a total of 23. No information about how many of these children are specific...
Source: The Autism Crisis - Category: Child Development Source Type: blogs