Insurance mandates increase autism rates because, in borderline cases, practitioners and parents push for a diagnosis that ensures a child receives coverage for the help the child and family need. The families of children with developmental disorders other than autism must often rely on broad laws such as the Individuals with Disabilities Education Act (IDEA), which vaguely states that each child must receive a “free and appropriate public education in the least restrictive environment.” IDEA’s implementation is underfunded by Congress and largely depends on each state’s interpretation of it. With such limited options for children with special needs, it makes sense that caring practitioners might push for a diagnosis that guarantees children receive the help they need over one without the same political power.

These factors were crystalized by the CDC’s changing methodology to measure autism rates. In 2013, the American Psychiatric Association narrowed its criteria for an autism diagnosis. In its 2018 and 2020 reports, however, the CDC used both the psychiatric association’s older broad diagnostic criteria and its newer narrow criteria, inflating rates. In its December 2021 report in MMWR, the agency went a step further, including not only children with autism diagnoses but also those with an autism billing code or a special education classification of autism. That meant a child didn’t even need a formal diagnosis of autism to be counted as a datapoint in the “autism epidemic.”