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Profound Autism Definition

The definition of autism has evolved over the years, creating an increasingly heterogeneous spectrum.

While the entire spectrum deserves recognition and support, profound autism is a term intended to provide clarification about autistic people who require 24/7 care throughout their lives. 


The Lancet Commission on the future of care and clinical research in autism

Published: December 6, 2021[1]

"Awareness of autism has grown monumentally over the past 20 years. Yet, this increased awareness has not been accompanied by improvements in services to support autistic individuals and their families. Many fundamental questions remain about the care of people with autism—including which interventions are effective, for whom, when, and at what intensity. The Lancet Commission on the future of care and clinical research in autism aims to answer the question of what can be done in the next 5 years to address the current needs of autistic individuals and families worldwide."

Lancet Commission Introduces a New Definition

The Commission proposes that the designation of profound autism be adopted as an administrative term to apply to children and adults:

  • Requiring 24-hour access to an adult who can care for them if concerns arise,
  • Being unable to be left completely alone in a residence and unable to take care of basic daily adaptive needs.

What the New Definition is Not

  • The term profound autism is not appropriate for young children.
  • It is not intended to describe other severe difficulties related to autism that might apply to individuals with extraordinary life circumstances, trauma, family conflict, scarcity of resources, or those with co-occurring mental health problems.

Centers for Disease Control Prevalence Study

Published April 2023[2]

Based on previous work by the Lancet Commission, the Centers for Disease Control released their first prevalence study on profound autism in April 2023.

The research concluded that:

  • The percentage of 8-year-old children with profound autism among those with autism was 26.7%. This means that 1 in 4 children with autism have profound autism.
  • Compared with children with non–profound autism, children with profound autism were more likely to be:
    • female;
    • from racial and ethnic minority groups;
    • of low socioeconomic status;
    • born preterm or with low birth weight;
    • have self-injurious behaviors;
    • have seizure disorders;
    • and have lower adaptive scores.

Pinning down profound autism for reliable research

Profound Autism Alliance is proud to be a funder of the Delphi project referenceD in this interview.

Profound Autism Alliance Medical and Scientific Advisory Committee member Dr. Matt Siegel was recently interviewed in The Transmitter about reaching a consensus regarding the term profound autism.

Clarity is imperative to ensure people with profound autism are included in research and have access to meaningful supports and services. 

Why the need for the term profound autism?

  • The use of the term profound autism is about clarity, not competition. People with profound autism consistently experience unique, devastating, and often unseen challenges that require solutions, not only for them but for their caregivers.
  • Research indicates that the proportion of studies that included those with profound autism has decreased significantly over time.[3] The continuing recognition of profound autism will open the doors to more inclusive research. Only then can targeted advocacy increase access to critically needed supports and services for this marginalized population.


Questions? Please email us at [email protected]

[1] Lord C, Charman T, Havdahl A, Carbone P, Anagnostou E, Boyd B, Carr T, de Vries PJ, Dissanayake C, Divan G, Freitag CM, Gotelli MM, Kasari C, Knapp M, Mundy P, Plank A, Scahill L, Servili C, Shattuck P, Simonoff E, Singer AT, Slonims V, Wang PP, Ysrraelit MC, Jellett R, Pickles A, Cusack J, Howlin P, Szatmari P, Holbrook A, Toolan C, McCauley JB. The Lancet Commission on the future of care and clinical research in autism. Lancet. 2022 Jan 15;399(10321):271-334. doi: 10.1016/S0140-6736(21)01541-5. Epub December 6, 2021. Erratum in: Lancet. 2022 Dec 3;400(10367):1926. P.M.I.D.: 34883054.

[2] Hughes MM, Shaw KA, DiRienzo M, et al. The Prevalence and Characteristics of Children With Profound Autism, 15 Sites, United States, 2000-2016. Public Health Reports. 2023;0(0). doi:10.1177/00333549231163551

[3] Stedman, Amy & Taylor, Briana & Erard, Michael & Peura, Christine & Siegel, Matthew. (2019). Are Children Severely Affected by Autism Spectrum Disorder Underrepresented in Treatment Studies? An Analysis of the Literature. Journal of Autism and Developmental Disorders. 49. 10.1007/s10803-018-3844-y.