(CNN) A survey of parents across the United States estimates that one in 40 children has autism spectrum disorder according to a study published Monday in the journal Pediatrics. In other words the condition was reported in 2.5 of children representing an estimated 1.5 million kids ages 3 to 17. A report released this year by the US Centers for Disease Control and Prevention estimated the prevalence at one in 59 children or about 1.7 based on 2014 data.