Autism Science Foundation Comments on Today’s CDC Data Showing Autism Prevalence Rate Rising to 1 in 54 from 1 in 59

NEW YORK — March 26, 2020 — The Centers for Disease Control and Prevention (CDC) today announced that 1 in 54 eight-year old children have been identified with autism, a rise from the 1 in 59 rate announced two years ago.

The increased prevalence rate announced today is based on a study of children who were 8 years old in 2016. The 1 in 59 number, reported in 2018, was based on a study of children who were 8 years old in 2014.

“The rise in prevalence is concerning, but more concerning to us right now is the fact that children with autism are sheltering in place due to coronavirus, and many are suffering tremendously due to severe disruptions in their routine and lack of access to mandated therapeutic services,” said Alison Singer, President of the Autism Science Foundation.

She continued: “The change from 59 to 54 is important, but right now we are focused on supporting every family’s ‘1.’ All families are facing obstacles, but our autism families are facing unique and unprecedented challenges far beyond what is typically being experienced in this country.”

The widespread social distancing initiatives are also impacting research efforts, according to Dr. Alycia Halladay, Chief Science Officer at the Autism Science Foundation.

“Universities across the country are understandably shuttered, which means that the majority of clinical research has decelerated and the pace of progress through which we will learn how to best treat children with autism has slowed just at the time that we learn prevalence has increased. At ASF, we are committed to supporting all autism families and all autism scientists during this challenging time.”

Other key points from the CDC Report include:

  • Boys were four times more likely to be identified with autism than girls.
  • Girls identified with autism were more likely to have an intellectual disability than boys.
  • Prevalence was the same in white and black children. Hispanic children are identified at a lower rate than black or white children.
  • A second report focused on 4-year-old children indicated that 84% of 4-year-olds had received a first developmental screening by 36 months, compared to 74% in the report two years ago. This screening increase is important because the earlier children are identified with autism, the sooner they can start receiving services.
  • Black and Hispanic children received evaluations at older ages than white children.

Media Contact
Sam Belden
Forefront Communications for Autism Science Foundation

PROBLEM/CONDITION: Autism spectrum disorder (ASD).


DESCRIPTION OF SYSTEM: The Autism and Developmental Disabilities Monitoring (ADDM) Network is an active surveillance system that provides estimates of the prevalence of autism spectrum disorder (ASD) among children aged 8 years whose parents or guardians reside within 11 ADDM sites in the United States (Arizona, Arkansas, Colorado, Georgia, Maryland, Minnesota, Missouri, New Jersey, North Carolina, Tennessee, and Wisconsin). ADDM surveillance is conducted in two phases. The first phase involves review and abstraction of comprehensive evaluations that were completed by professional service providers in the community. Staff completing record review and abstraction receive extensive training and supervision and are evaluated according to strict reliability standards to certify effective initial training, identify ongoing training needs, and ensure adherence to the prescribed methodology. Record review and abstraction occurs in a variety of data sources ranging from general pediatric health clinics to specialized programs serving children with developmental disabilities. In addition, most of the ADDM sites also review records for children who have received special education services in public schools. In the second phase of the study, all abstracted information is reviewed systematically by experienced clinicians to determine ASD case status. A child is considered to meet the surveillance case definition for ASD if he or she displays behaviors, as described on one or more comprehensive evaluations completed by community-based professional providers, consistent with the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) diagnostic criteria for autistic disorder; pervasive developmental disorder-not otherwise specified (PDD-NOS, including atypical autism); or Asperger disorder. This report provides updated ASD prevalence estimates for children aged 8 years during the 2014 surveillance year, on the basis of DSM-IV-TR criteria, and describes characteristics of the population of children with ASD. In 2013, the American Psychiatric Association published the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), which made considerable changes to ASD diagnostic criteria. The change in ASD diagnostic criteria might influence ADDM ASD prevalence estimates; therefore, most (85%) of the records used to determine prevalence estimates based on DSM-IV-TR criteria underwent additional review under a newly operationalized surveillance case definition for ASD consistent with the DSM-5 diagnostic criteria. Children meeting this new surveillance case definition could qualify on the basis of one or both of the following criteria, as documented in abstracted comprehensive evaluations: 1) behaviors consistent with the DSM-5 diagnostic features; and/or 2) an ASD diagnosis, whether based on DSM-IV-TR or DSM-5 diagnostic criteria. Stratified comparisons of the number of children meeting either of these two case definitions also are reported.

RESULTS: For 2014, the overall prevalence of ASD among the 11 ADDM sites was 16.8 per 1,000 (one in 59) children aged 8 years. Overall ASD prevalence estimates varied among sites, from 13.1-29.3 per 1,000 children aged 8 years. ASD prevalence estimates also varied by sex and race/ethnicity. Males were four times more likely than females to be identified with ASD. Prevalence estimates were higher for non-Hispanic white (henceforth, white) children compared with non-Hispanic black (henceforth, black) children, and both groups were more likely to be identified with ASD compared with Hispanic children. Among the nine sites with sufficient data on intellectual ability, 31% of children with ASD were classified in the range of intellectual disability (intelligence quotient [IQ] <70), 25% were in the borderline range (IQ 71-85), and 44% had IQ scores in the average to above average range (i.e., IQ >85). The distribution of intellectual ability varied by sex and race/ethnicity. Although mention of developmental concerns by age 36 months was documented for 85% of children with ASD, only 42% had a comprehensive evaluation on record by age 36 months. The median age of earliest known ASD diagnosis was 52 months and did not differ significantly by sex or race/ethnicity. For the targeted comparison of DSM-IV-TR and DSM-5 results, the number and characteristics of children meeting the newly operationalized DSM-5 case definition for ASD were similar to those meeting the DSM-IV-TR case definition, with DSM-IV-TR case counts exceeding DSM-5 counts by less than 5% and approximately 86% overlap between the two case definitions (kappa = 0.85).

INTERPRETATION: Findings from the ADDM Network, on the basis of 2014 data reported from 11 sites, provide updated population-based estimates of the prevalence of ASD among children aged 8 years in multiple communities in the United States. The overall ASD prevalence estimate of 16.8 per 1,000 children aged 8 years in 2014 is higher than previously reported estimates from the ADDM Network. Because the ADDM sites do not provide a representative sample of the entire United States, the combined prevalence estimates presented in this report cannot be generalized to all children aged 8 years in the United States. Consistent with reports from previous ADDM surveillance years, findings from 2014 were marked by variation in ASD prevalence when stratified by geographic area, sex, and level of intellectual ability. Differences in prevalence estimates between black and white children have diminished in most sites, but remained notable for Hispanic children. For 2014, results from application of the DSM-IV-TR and DSM-5 case definitions were similar, overall and when stratified by sex, race/ethnicity, DSM-IV-TR diagnostic subtype, or level of intellectual ability.

PUBLIC HEALTH ACTION: Beginning with surveillance year 2016, the DSM-5 case definition will serve as the basis for ADDM estimates of ASD prevalence in future surveillance reports. Although the DSM-IV-TR case definition will eventually be phased out, it will be applied in a limited geographic area to offer additional data for comparison. Future analyses will examine trends in the continued use of DSM-IV-TR diagnoses, such as autistic disorder, PDD-NOS, and Asperger disorder in health and education records, documentation of symptoms consistent with DSM-5 terminology, and how these trends might influence estimates of ASD prevalence over time. The latest findings from the ADDM Network provide evidence that the prevalence of ASD is higher than previously reported estimates and continues to vary among certain racial/ethnic groups and communities. With prevalence of ASD ranging from 13.1 to 29.3 per 1,000 children aged 8 years in different communities throughout the United States, the need for behavioral, educational, residential, and occupational services remains high, as does the need for increased research on both genetic and nongenetic risk factors for ASD.

You may have heard the news: The prevalence of autism is 1:40 according to an email survey of parents. However, there’s more information in the study that’s worthy of consideration: The high rate of unmet mental health needs in those with ASD. Learn more on the ASF podcast. Read more about the study.

The Centers for Disease Control and Prevention (CDC) estimates autism prevalence at 1 in 59 children based on data from the CDC’s Autism and Developmental Disabilities Monitoring (ADDM) Network – a tracking system that provides estimates of the prevalence and characteristics of autism spectrum disorder among more than 300,000 8-year-old children. The ADDM Network estimates are combined from 11 communities within Arizona, Arkansas, Colorado, Georgia, Maryland, Minnesota, Missouri, New Jersey, North Carolina, Tennessee, and Wisconsin. The 11 communities surveyed in this report represent about 8 percent of 8-year-old children in the United States.

You can read more in the official CDC press release on ASF’s website here. You can read the official CDC analysis in a report published today in the CDC’s Morbidity and Mortality Weekly Report (MMWR) Surveillance Summary.

A new study by the CDC, including Dr. Matthew Maenner, ASF Grantee ’10, found that 95% of children with autism have at least one psychiatric or medical comorbidity, which may have a role in age of first evaluation—the more comorbid conditions, the earlier the first evaluation for ASD. Read the study here.

This week’s ASF podcast takes a look at the prevalence rate of autism diagnoses. Two national datasets have shown no further increase in autism prevalence in the last few years of looking. Also, folic acid proves to show an effect on the probability of not just an autism diagnosis but also autism symptoms, especially important for women taking anti epileptic medications for seizures and bipolar depression. Listen to the podcast here.