Illustration by Laurène Boglio

By the Numbers: Unequal ABA access, autism incidence by insurance type, criminal charges counts

In this edition of By the Numbers, we discuss geographic disparities in access to behavior therapy, autism incidence among the privately or publicly insured and the rarity of criminal charges against autistic people in New Zealand.

It’s 2022 and By the Numbers is back. Last week, we released the Autism Drug Trial Tracker, an interactive tool to explore hundreds of clinical trials for autism and related conditions. All the code and data are open source, and we hope it proves useful to the autism research community. We’ll update the tool regularly, as new data become available.

Let us know what you think of the newsletter, or the drug trial tracker, at [email protected]. Thanks for reading.


Between 2018 and 2021, the number of board-certified behavioral analysts (BCBAs) — who provide the standard autism therapy applied behavior analysis — jumped from 27,320 to 45,103 in the United States, a 65 percent increase, according to a new study. But that rapid growth was uneven. Nearly half the counties in the U.S. still lack a single BCBA, and most of the growth is concentrated in large, coastal cities.

The study relied on data from the U.S. Department of Education and an online registry of certified behavioral analysts to determine the number of licensed providers in 3,318 counties and county equivalents, such as parishes and independent cities, across the U.S. Of those, just 266 added a BCBA during the study period.

The findings appeared in the Journal of Autism and Developmental Disorders earlier this month.


About 1.6 and 1.3 percent of children covered by public or private insurance, respectively, are diagnosed with autism by age 8. That’s according to a new study in JAMA Psychiatry that analyzed birth cohort data for more than 2 million publicly insured and more than 1.3 million privately insured children.

The researchers also stratified the data based on birth year, maternal age and race. More children born in recent years appeared to be diagnosed than those born earlier. And white publicly insured children in the study were twice as likely to be diagnosed with autism as Black, Asian or Hispanic publicly insured children.


Autistic people are 38 percent less likely to be proceeded against, 40 percent less likely to be charged and 44 percent less likely to be convicted following a police interaction than their non-autistic peers in the island nation of New Zealand. Autistic people are incarcerated at a slightly higher rate than non-autistic people, though.

The data include 1,197 people with autism and 147,879 without autism who had a police interaction when they were between 17 and 25 years old. The study, published in Autism in December, claims to be the first to examine pathways through a criminal justice system for a national sample of young adults with or without autism.

A prior study of 431 male prisoners in the U.S., by contrast, found that 4.4 percent of them had autism, which is double the prevalence in the general population. Spectrum has previously covered the challenges of being incarcerated and autistic.


Spectrum index:

8.1: The additional number of autism diagnoses per 1,000 children per quarter when screening for the condition using questionnaires and diagnostic evaluations. Spanish-speaking families saw the greatest benefit from this multi-pronged approach. The results, based on data from the Massachusetts Department of Public Health, were published in JAMA Pediatrics in January.

95: The percentage of children accurately screened as not having autism using a 10-item version of the Quantitative Checklist for Autism in Toddlers (Q-CHAT), according to a study in Molecular Autism in January. That specificity bests two revised versions of the Modified Checklist for Autism in Toddlers (M-CHAT), the predominant tool used to screen toddlers.

13: The percentage of autistic children who were referred for applied behavior analysis (ABA) but never received it, according to data from a single healthcare clinic in Southern California. The study also found that 66 percent of children who initiated ABA continued for 12 months, and less than half completed the recommended 24 months of therapy. The work was published in the Journal of Developmental and Behavioral Pediatrics in January.