This study was designed to evaluate the hypothesis that the prevalence of autism spectrum disorder (ASD) among children in the United States is positively associated with socioeconomic status (SES).

The higher rates of diagnosed autism among the wealthy has long been thought to be a result of higher rates of diagnosis (or “diagnostic?ascertainment bias”) – i.e., wealthier families having better access to those who diagnose autism. However, a new paper argues that the disease itself might actually be more common at the higher end of the income spectrum. The paper relied on “abstracted data from records of multiple educational and medical sources to determine the number of children who appear to meet the ASD case definition, regardless of pre-existing diagnosis. Clinicians determine whether the ASD case definition is met by reviewing a compiled record of all relevant abstracted data.” Within all ethnic groups, wealthier parents were more likely to have autistic children, and the pattern held for undiagnosed autistic children as well. Neuroskeptic hypothesizes that paternal age may be partially responsible for the disparity. (HT: Marginal Revolution)[%comments]