Assessment & Research

Prevalence of Autism Spectrum Disorder Severity Levels From the Fifth Edition of the Diagnostic and Statistical Manual (DSM-5) in the Autism and Developmental Disabilities Monitoring Network.

Russell et al. (2026) · Journal of autism and developmental disorders 2026
★ The Verdict

Clinician-chosen DSM-5-TR autism levels mirror real test score gradients—use them to set service intensity and to flag bright kids who still struggle with daily living.

✓ Read this if BCBAs writing diagnostic evaluations or treatment plans for school-age clients.
✗ Skip if Clinicians who only see adults or who do not assign DSM-5-TR levels.

01Research in Context

01

What this study did

The team looked at young learners in the Autism and Developmental Disabilities Monitoring Network.

Doctors had already given each child a DSM-5-TR support level: 1, 2, or 3.

Researchers checked if those levels matched the kids’ IQ scores, daily-living scores, and autism symptom totals.

02

What they found

Level the kids had the lowest IQs, lowest adaptive scores, and most autism symptoms.

Level the kids had the highest scores on all three measures.

Girls and boys with the same level looked almost identical, so sex did not predict level.

03

How this fits with other research

Schaaf et al. (2015) warned that 25-a large share of high-functioning clients lose the ASD label under DSM-5. The new data show that when clinicians do assign a level, it lines up well with test scores, so the levels are not random.

Pathak et al. (2019) found that higher-IQ children often have bigger IQ-adaptive gaps. Kaplan-Kahn et al. (2026) confirm this: many Level the kids look bright on paper yet still need daily-living support.

Deserno et al. (2017) followed teens into adulthood and saw the same gap widen with anxiety or depression. The 2026 study shows the gap is already visible at age 8, so early adaptive training is key.

04

Why it matters

You can trust the DSM-5-TR level you write in your report; it carries real information about IQ, adaptive skills, and symptom load. Use the level to justify hours: Level 3 equals intensive comprehensive care, Level 1 equals focused social-adaptive coaching. Do not let a high IQ talk you out of adaptive goals—watch the gap and start teaching daily skills early.

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Pull your last Level 1 case, graph IQ vs. Vineland, and add adaptive goals if the gap is >20 points.

02At a glance

Intervention
not applicable
Design
other
Sample size
136
Population
autism spectrum disorder
Finding
not reported

03Original abstract

The diagnostic criteria for autism spectrum disorder in the DSM-5-TR features the option to designate levels of support for social communication (SC) and restricted, repetitive behaviors (RRB). These levels are conceptual in nature, but research indicates standardized assessment outcomes correspond with clinician-assigned levels of support. The purpose of the present study was to identify factors that influence designated levels of support for SC and RRBs when diagnosing autism. Standardized assessment scores across intellectual functioning, adaptive skills, and ASD symptomology were analyzed to determine corresponding levels of support in SC and RRBs assigned by clinicians for 136 autistic children following a comprehensive diagnostic evaluation. At diagnosis, approximately 46% of participants were described as needing substantial support (Level 2) for SC and 49% were described as needing substantial support (Level 2) for RRB. There was a consistent pattern of higher to lower intellectual and adaptive functioning needing Level 1-Level 3 support. Autism assessment results followed a gradient of fewer to greater autism symptoms from Level 1 to Level 3 support. Findings indicated clinician-assigned levels of support for SC and RRB were associated with intellectual functioning, adaptive functioning, autism symptomology, and age, but not sex.

Journal of autism and developmental disorders, 2026 · doi:10.1007/s10803-013-1882-z