Association for Public Policy Analysis & Management

Most states have passed insurance mandates requiring commercial health plans to cover services for children with autism. Insurers have expressed concerns that these mandates will increase the number of children diagnosed with autism (treated prevalence) and therefore increase costs associated with their care. No published studies have addressed this question.  Our research objective was to examine whether implementing autism insurance mandates increases the number of commercially-insured children diagnosed with autism. To examine treated prevalence before and after the implementation of state autism mandates, we used inpatient and outpatient facility, and professional procedure claims data from the Health Care Cost Institute (HCCI) from 2008 through 2012. HCCI data were provided voluntarily from three of the nation’s largest insurers: United HealthCare, Aetna and Humana. These commercial claims represent more than 50 million individuals per year in all 50 states and the District of Columbia. An important aspect of the HCCI data is that they indicate whether an enrollee had commercial insurance coverage through a firm that was self-insured or fully-insured. To evaluate the effect of state autism laws on treated prevalence, we used a difference-in-differences approach with state and year fixed effects that compared treated prevalence within states before and after mandate implementation and between groups of children who would and would not be affected by the laws based on the source of their health insurance and their age.  We included children ages 0-21 insured by one of these insurers during the study period.

 Adjusted treated prevalence among eligible children in mandate states was 2.7 per 1000, and 2.4 per 1000 among children in non-mandate states (p = .006). The average increase in treated prevalence attributable to the mandates was 0.3/1000 over the study period (95% CI: .2 to .4 /1000; p<0.001). Mandates in place longer had a larger effect on treated prevalence. Average increase in treated prevalence attributable to the mandate was 0.2/1000 (95% CI: .1 to .4 /1000; p = .02) in the first year following implementation, 0.4/1000 (95% CI: .2 to .6 /1000; p = .011) in the second year and 0.4/1000 (95% CI: .2 to .6 /1000; p = .007) ≥3 years following implementation. 

 This study showed that implementing state autism insurance mandates resulted in modest increases in treated prevalence, which grew somewhat two years post-implementation. However, even three years after implementation, treated prevalence was much lower than community prevalence estimates. This finding may allay concerns that mandates will substantially increase insurance costs, but suggests that many commercially-insured children with autism remain undiagnosed or are being treated only through publicly-funded systems.