In April 2018, the Centers for Disease Control and Prevention (CDC) released a report estimating the prevalence of autism spectrum disorder (ASD) in the United States at 1 in 59 children. The figure was based on a 2014 survey of eight-year-old children across 11 residential communities in the country, so clearly it was out of date. It was not a valid estimate of the prevalence of ASD in the U.S. in 2017 or 2018,1 and we don’t know what the figure is for 2019.
As pediatrician Bob Sears, MD notes, the “main drawback” of this methodology by the CDC is that it takes “many years to research and report data this way, and the information is very old by the time we get it.” Dr. Sears adds:
For example, for kids born in 2004, the CDC had to wait until they were are 8 years old (2012), then take two years to gather the data on diagnosis rates, then publish it. So, we didn’t learn the rate of autism in these kids until 10 years after they are born.2
So long as the methodology (notably the four-year lag time and the focus on eight-year-olds) used by the CDC is known and understood, it is not a problem. The public just needs to be aware that the CDC’s autism prevalence figure is always going to be out of date by the time it is released.
A better source for more current information on the prevalence of autism in the U.S. is the National Health Center for Health Statistics (NCHS), which is the U.S. government’s principal health statistics agency.3
The NCHS conducts nationwide surveys to tabulate health data on different topics, including estimates for how prevalent autism is among children. In 2017, the NCHS published health data for 2014-2016 which pegged the prevalence of autism for children aged 3-17 years at 1 in 36 in 2016, compared to 1 in 43 in 2015 and 1 in 45 in 2014.2
As of 2017, the 1 in 36 figure appeared to be the most current estimate from the U.S. government for the prevalence of autism, not the 1 in 59 figure that has been so commonly cited by the media and other sources for the past year.4 5 6 7
To make things slightly more confusing, there is a new autism prevalence figure in a study published in the journal Pediatrics in December 2018 based on the 2016 National Survey of Children’s Health (NSCH). That study estimates that 1 in 40 children have autism. The NSCH is funded and directed by the Maternal and Child Health Bureau (MCHB) of the Health Resources and Services Administration (HRSA).8 9 10
1 Parpia R, Fisher BL. CDC: Autism Rate Going Up. The Vaccine Reaction May 28, 2018.
2 Sears R. Autism Rate Jumps to 1 in 36 Children, 1 in 28 Boys. AskDrSears.
3 National Center for Health Statistics (NCHS). U.S. National Library of Medicine.
4 University of Central Florida. Processed foods and effect on developing fetus’ brain: Autism link? Science Daily June 20, 2019.
5 How Common is Autism? Autism Science Foundation.
6 Staff News Writer. Wearable tech supports home therapy for kids with autism. American Medical Association June 21, 2019.
7 Max. I Have Autism and I’m Offended by the Anti-Vax Movement. Newsweek June 19, 2019.
8 Mozes A. Report: Autism Rate Rises to 1 in 40 Children. HealthDay Nov. 26, 2018.
9 Kogan MD, Vladutiu CJ, Schieve LA, Ghandour RM, Blumberg SJ, Zablotsky B, Perrin JM, Shattuck P, Kuhlthau KA, Harwood RL, Lu MC. The Prevalence of Parent-Reported Autism Spectrum Disorder Among US Children. Pediatrics December 2018; 142(6).
10 The National Survey of Children’s Health. Data Resource Center for Child & Adolescent Health.