Researchers at the Johns Hopkins Bloomberg School of Public Health contributed to a new U.S. Centers for Disease Control and Prevention (CDC) report that finds the prevalence of autism spectrum disorder (ASD) among 11 surveillance sites as one in 59 among children aged 8 years in 2014 (or 1.7 percent). This marks a 15 percent increase from the most recent report two years ago, and the highest prevalence since the CDC began tracking ASD in 2000. Consistent with previous reports, boys were four times more likely to be identified with ASD than girls. The rate is one in 38 among boys (or 2.7 percent) and one in 152 among girls (or 0.7 percent).
ASD is a developmental disorder characterized by social and communication impairments, combined with limited interests and repetitive behaviors. Early diagnosis and intervention are key to improving learning and skills. Rates have been rising since the 1960s, but researchers do not know how much of this rise is due to an increase in actual cases. There are other factors that may be contributing, such as: increased awareness, screening, diagnostic services, treatment and intervention services, better documentation of ASD behaviors and changes in diagnostic criteria.
For this new report, the CDC collected data at 11 regional monitoring sites that are part of the Autism and Developmental Disabilities Monitoring (ADDM) Network in the following states: Arizona, Arkansas, Colorado, Georgia, Maryland, Minnesota, Missouri, New Jersey, North Carolina, Tennessee and Wisconsin. The Maryland monitoring site is based at the Johns Hopkins Bloomberg School of Public Health in Baltimore.