Individuals with autism spectrum disorder (ASD) have higher rates of co-occurring diagnoses and use of psychotropic medication prescriptions than people with other developmental disabilities. Few studies have examined these trends in samples of people with intellectual and developmental disabilities (IDD) with and without ASD. Using a random…

We investigated if shifts in the coding of qualifying conditions in the California Department of Developmental Services (DDS) have contributed to the increase in California children with autism observed in recent years. Qualifying condition codes for mental retardation (MR) and autism in DDS electronic files were compared to hard-copy records for…