CDC Prevalence Update FAQ

1. What are the results of the CDC autism prevalence update?

This week, the CDC updated its biennial report of autism prevalence among the nation’s children, estimating that 1 in 36 children in the U.S. is on the autism spectrum.  

2. What are the findings of the report?

Key findings include:

  • One in 36 children, or 2.7% of 8-year-old children, in the U.S. was diagnosed with ASD in 2020, increasing from 2018 when the estimate was 1 in 44.
  • The rate of autism per 1000 was higher in BNH (29.3), Hispanic (31.6), and A/PI (33.4) compared to WNH children (24.3), indicating an improvement in outreach, screenings and de-stigmatization of autism diagnosis among minority communities.
  • BNH autistic children were more likely than WNH and Hispanic autistic children to have a co-occurring intellectual disability. Autistic girls were also more likely to have a co-occurring intellectual disability when compared to autistic boys. Both findings indicate an undercounting of autism among BNH and female children, highlighting the need for greater research on the age at which BNH children and girls without intellectual disabilities receive autism evaluations and diagnoses.
  • The COVID-19 pandemic limited data collection, potentially leading to an under-reporting of prevalence and reinforcing the need to explore long-term impacts of the COVID-19 pandemic on evaluation and diagnosis of autism.

3. What do these results mean for the autism community?

The increase reinforces progress in awareness and advocacy for early identification and diagnosis among all groups, but also reiterates the need for a significant increase in funding for autism research and services to be provided across the spectrum and lifespan, particularly in diverse communities where prevalence numbers were greater than those indicated by previous studies.

4. What is the research behind this report?

The report is based on the active surveillance across 11 monitoring sites in the United States for 8-year-old children in 2020.

5. Why are the numbers from 2020?

It takes several years to gather and analyze the records and to go through the review process. The numbers from the previous prevalence report (in 2021) were from 2018. 

6. Why is prevalence higher in some states than in others?

Differences remain in the frequency of autism diagnosis between the CDC’s monitoring sites. This may be due to how autism is diagnosed and documented in different communities, state and regional differences in children’s access to autism screening, as well as differences in the CDC’s access to the school and medical records used to estimate prevalence. 

Furthermore, the COVID-19 pandemic limited the CDC’s limited data collection, potentially leading to an under-reporting of prevalence and reinforcing the need to explore long-term impacts of the COVID-19 pandemic on evaluation and diagnosis of autism.

7. Why are there more cases of autism?

We know there is an increase in the number of people with autism, but the reasons for some of the increases are unknown. That is why increased research into the causes of autism is so critical. We do know some factors that have contributed include the increased awareness of autism symptoms and screening as well as the diagnostic changes and data collection approach.

8. Do the results reflect an increase in early screenings?

The new report demonstrates real progress in early screening and diagnosis, the result of more than a decade of awareness and advocacy work by Autism Speaks and other organizations.

9. What is the difference in prevalence rates between black, white and Hispanic children?

For the first time, the CDC report reveals higher prevalence rates per 1000 among Black non-Hispanic (29.3), Hispanic (31.6), and Asian or Pacific Islander (33.4) compared to White non-Hispanic (24.3), indicating an improvement in outreach, screenings and de-stigmatization of autism diagnosis among minority communities, as well as the need for a significant increase in funding for autism research and services to be provided in diverse communities.

10. What is the difference in prevalence rates between boys and girls?

Boys are four times as likely to be diagnosed as girls, holding steady from previous reports. This indicates the need for more research to understand the gap in prevalence and ensure girls on the spectrum are receiving the care they need. 

Autistic girls were also more likely to have a co-occurring intellectual disability when compared to autistic boys, reinforcing an undercounting of autism among girls and highlighting the need for greater research on the age at which girls without intellectual disabilities receive autism evaluations and diagnoses.

11. Do vaccines play a role?

Each family has a unique experience with an autism diagnosis, and for some it corresponds with the timing of their child’s vaccinations. At the same time, over the last two decades there has been extensive research to determine whether there is a link between childhood vaccinations and autism. The result of this research is that vaccines do not cause autism.

12. How is Autism Speaks supporting the increase in early screenings?

Research shows that early screening and timely intervention can improve a child’s overall development and future outcomes. We continue to work on closing the diagnosis gap, with a special focus on high need, underserved area populations by empowering parents, educating physicians and increasing access to interventions and supports.

Here are a few of our recent accomplishments: 

  • Initiated a bilingual public service campaign in collaboration with the Ad Council to help close the diagnosis gap, especially in minority populations. As a result, nearly half a million families have accessed the M-CHAT autism screening questionnaire on Autism Speaks’ website.
  • Supported the creation of the Caregiver Skills Training program, and e-CST program (accessible to anyone with an internet connection) in collaboration with the World Health Organization, with the goal of teaching caregivers, through both virtual and in-person modules, how to use play and everyday routines to help their child share activities, expand their communication, learn new skills.
  • Intentional, targeted outreach to underserved communities, as well as training culturally informed service providers can make a difference in delivering accessible quality care to underserved communities. Autism Speaks Autism Care Network, a partnership of 24 participating medical centers across the U.S. and Canada, use patient insights to improve person and family-centered autism care in communities across North America to achieve this goal.
  • Played a pivotal role in securing laws and regulations requiring coverage of autism services, including applied behavior analysis (ABA). We continue to successfully advocate to close gaps in autism coverage requirements and to help families when they are being denied access to medically necessary care.

13. Does Autism Speaks help fund research to increase early screenings?

Autism Speaks is working tirelessly to fuel research that would allow earlier diagnosis and intervention; advocacy with and for the autism community to ensure access to care; and programs and services that allow our constituents to reach their full potential.

Despite the progress made, we know that more is needed. We will continue to champion the importance of early screening and intervention for all children, as we know this leads to better outcomes and increases the opportunity for people with autism to thrive.

14. How does Autism Speak work with policymakers to increase research?

Autism Speaks calls on legislators, public health agencies and the National Institutes of Health to advance research to better understand the continued increase in prevalence and the co-occurring medical conditions that may accompany autism. 

In doing so, the organization urges policy makers to double the federal funding of autism research, in accordance with the guidance of the Interagency Autism Coordinating Committee (IACC), and to advance policies that better provide services and supports for early intervention, education, transition to adulthood, employment and community living.  

15. What resources does Autism Speaks offer for early diagnosis? 

The Autism Response Team is available to respond to questions at 1-888-AUTISM2 (1-888-288-4762), en Español at 1-888-772-9050 and via email at help@autismspeaks.org.

Autism Speaks also offers the following resources:

16. How can I get involved with Autism Speaks?  

Please consider giving today. Eighty-nine cents of every dollar helps fund critical research, advocacy, programs and services for people with autism. 

17. Where can I find more details about the findings and analysis of the CDC autism prevalence update report?

The entire report is available to view at the Community Report on Autism page.