Autism spectrum disorder controversy

2025-11-06

Published

November 13, 2025

Modified

November 13, 2025

Source: https://xkcd.com/3117/

About

This page documents the lab’s work on the question of what factors contribute to the rise in diagnoses of Autism Spectrum Disorder (ASD).

Background

On October 29, 2025, U.S. Secretary of Health and Human Services (HHS) Robert F. Kennedy, Jr. said that there is not “sufficient” evidence to link use of Tylenol (acetaminophen) during pregnancy to autism (Ramaswamy, 2025).

In April, the Centers for Disease Control released a report (Shaw et al., 2025) from the Autism and Developmental Disabilities Monitoring (ADDM) Network (CDC, 2025).

Here is a figure to capture some of the associations:

flowchart TD
  B(sex) ---> A[ASD_dx]
  C(med household income) ---> A
  D(race) ---> A
  E(location) ---> A
  F(age_2022) ---> A
  A --- G[intellectual disability]
  D ---> G
  E ---> G
  F ---> G
  H(age_dx) ---> A
  E ---> I(use of ASD test)
  I ---> A
  J{health literacy} ---> A

Autism diagnosis (dx) measures

Shaw et al. (2025) assigned an autism diagnosis to children who met one of the following criteria:

  1. an ASD diagnostic statement in a comprehensive developmental evaluation, 2) autism special education eligibility, or 3) an ASD ICD-9 code in the 299 range or ICD-10 code of F84.0, F84.3, F84.5, F84.8, or F84.9. Children aged 4 years were classified as having suspected ASD if they did not meet the criteria for ASD but had an evaluator’s suspicion of ASD documented in a comprehensive developmental evaluation.
  • Autism Diagnostic Observation Schedule (ADOS), “(ADOS®-2) autism diagnostic observation schedule, second edition” (n.d.)
  • Autism Spectrum Rating Scales (ASRS), Naglieri (n.d.)
  • Childhood Autism Rating Scale (CARS), “(CARS®2) childhood autism rating scale, second edition” (n.d.)
  • Gilliam Autism Rating Scale (GARS), Gilliam (n.d.)
  • Social Responsiveness Scale (SRS), “(SRS™-2) social responsiveness scale, second edition” (n.d.)
  • Autism Diagnostic Interview-Revised (ADI-R), “(ADI®-R) autism diagnostic Interview–Revised” (n.d.)
Note

All of the tests are available only to administrators who pay for the testing materials.

Here is a paper that compares the ADOS to the CARS: Park, Yi, Yoon, & Hong (2018).

Autism Speaks promotes this parent-completed survey: “M-CHAT™ - autism screening” (2015).

Data by state

The Shaw et al. (2025) supplemental data are here.

Shaw et al. (2025) Supplemental Data. The width of the state-level prevalence estimates is due to different sample sizes. See Table 1 for more specifics about the state-level samples.

References

(ADI®-R) autism diagnostic Interview–Revised. (n.d.). Retrieved November 6, 2025, from https://www.wpspublish.com/adi-r-autism-diagnostic-interviewrevised.html
(ADOS®-2) autism diagnostic observation schedule, second edition. (n.d.). Retrieved November 6, 2025, from https://www.wpspublish.com/ados-2-autism-diagnostic-observation-schedule-second-edition
(CARS®2) childhood autism rating scale, second edition. (n.d.). Retrieved November 6, 2025, from https://www.wpspublish.com/cars-2-childhood-autism-rating-scale-second-edition.html
CDC. (2025, June 10). Autism and developmental disabilities monitoring (ADDM) network. Retrieved November 6, 2025, from https://www.cdc.gov/autism/addm-network/index.html
Gilliam, J. E. (n.d.). GARS-3 - gilliam autism rating scale. Retrieved November 6, 2025, from https://www.pearsonassessments.com/en-us/Store/Professional-Assessments/Behavior/Gilliam-Autism-Rating-Scale-%7C-Third-Edition/p/100000802?srsltid=AfmBOoqDkBK9lPtJC1cf45g5u71bUWlFP3-ReJXBXwsujJdd23JLcn43
M-CHAT™ - autism screening. (2015, February 20). Retrieved November 13, 2025, from https://www.mchatscreen.com/
Naglieri, J. A. (n.d.). Autism spectrum rating scales. Retrieved November 6, 2025, from https://www.pearsonassessments.com/en-us/Store/Professional-Assessments/Behavior/Autism-Spectrum-Rating-Scales/p/100000354?srsltid=AfmBOoqqodME3hIhB_eJ4QsHX15IMhqHlubjSZCb3_hj7JCQeJYqFtgX
Park, H. S., Yi, S. Y., Yoon, S. A., & Hong, S.-B. (2018). Comparison of the autism diagnostic observation schedule and childhood autism rating scale in the diagnosis of autism spectrum disorder: A preliminary study. Journal of Korean Academy of Child and Adolescent Psychiatry, 29, 172–177. https://doi.org/10.5765/jkacap.180015
Ramaswamy, S. V. (2025, October 29). Health secretary RFK jr. Says there’s ’not sufficient’ proof to show tylenol causes autism. USA Today. USA TODAY. Retrieved from https://www.usatoday.com/story/news/politics/2025/10/29/health-chief-insufficient-data-tylenol-causes-autism/86972118007/
Shaw, K. A., Williams, S., Patrick, M. E., Valencia-Prado, M., Durkin, M. S., Howerton, E. M., … Maenner, M. J. (2025). Prevalence and early identification of autism spectrum disorder among children aged 4 and 8 years - autism and developmental disabilities monitoring network, 16 sites, united states, 2022. MMWR Surveillance Summaries, 74, 1–22. https://doi.org/10.15585/mmwr.ss7402a1
(SRS™-2) social responsiveness scale, second edition. (n.d.). Retrieved November 6, 2025, from https://www.wpspublish.com/srs-2-social-responsiveness-scale-second-edition.html