In Prevalence of autism spectrum disorders and influence of country of measurement and ethnicity , the authors look at ASD prevalence by country and ethnicity. They hypothesize that “methodological factors, socioeconomic variables, and bias” play a role in the variability in autism prevalence.
The disparities by geography and by ethnicity within the data reported within the U.S. has been a big concern of mine for some time. Clearly there is not an obvious difference between, say, New Jersey (with an estimated prevalence of 10.6/1,000) and Alabama (with an estimated prevalence of 6/1,000) to account for the large difference in estimated prevalence.
In Racial Disparities in Community Identification of Autism Spectrum Disorders Over Time; Metropolitan Atlanta, Georgia, 2000-2006. African American (non Hispanic Black) students are less likely than Non Hispanic White students to be identified with “less severe” ASD’s. This even after controlling for socioeconomic status.
Racial Disparities in Community Identification of Autism Spectrum Disorders Over Time; Metropolitan Atlanta, Georgia, 2000-2006.
As a society, we have decided that autistic students often need educational supports distinct from those of children with other disabilities. Clearly if we are to serve our students appropriately, we should be accurately identifying each student’s disability (where they exist). The fact that we are not uniform in identifying autistic students indicates that we have far to go in this regard.