Direct answer
Yes, DSM-5 autism support levels (Level 1: requiring support, Level 2: requiring substantial support, Level 3: requiring very substantial support) can change over time. Research by Lord et al. (2015) found that approximately 9% of children initially diagnosed with autism no longer met diagnostic criteria by adulthood. More commonly, support levels shift: children receiving effective early intervention may move from Level 2 to Level 1. In Ontario, OAP services are based on clinical needs, not solely on diagnostic level.
Start with the short answer, then reveal deeper context where helpful.
DSM-5 support levels are meant to describe current functioning, not a permanent classification. A child diagnosed at Level 3 (requiring very substantial support) at age 3 may, after years of intensive intervention, function at Level 2 or even Level 1 by school age. Conversely, some individuals experience increased support needs during transitions (puberty, school changes, employment) or when compensatory strategies become insufficient.
OAP core clinical funding is based on clinical need as determined by your child's clinical team, not solely on the diagnostic level assigned at initial assessment. If your child's needs have changed significantly, discuss a clinical plan update with your BCBA or psychologist. A formal re-assessment may be recommended to document changes.
DSM-5 support levels are meant to describe current functioning, not a permanent classification. A child diagnosed at Level 3 (requiring very substantial support) at age 3 may, after years of intensive intervention, function at Level 2 or even Level 1 by school age. Conversely, some individuals experience increased support needs during transitions (puberty, school changes, employment) or when compensatory strategies become insufficient.
Level changes do not mean the autism itself has changed. Rather, the individual's ability to navigate their environment with available supports has shifted. Factors influencing level changes include early intervention quality, co-occurring conditions (anxiety, ADHD), environmental demands, and the development of compensatory strategies.
OAP core clinical funding is based on clinical need as determined by your child's clinical team, not solely on the diagnostic level assigned at initial assessment. If your child's needs have changed significantly, discuss a clinical plan update with your BCBA or psychologist. A formal re-assessment may be recommended to document changes.
For adults, a level change may affect workplace accommodation requests, ODSP eligibility reviews, or guardianship considerations. Updated documentation from a psychologist reflecting current functioning is advisable when support needs have significantly changed. The original diagnosis is not invalidated — the assessment simply documents the current presentation.
Research
Lord et al. (2015), "Autism From 2 to 9 Years of Age," Archives of General Psychiatry, 63(6), 694-701
APA
American Psychiatric Association — DSM-5 Severity Levels for Autism Spectrum Disorder (2013)
DSM-5 classifies autism into 3 support levels. Level 1 requires support, Level 2 substantial support, Level 3 very substantial support. Learn the differences.
A comprehensive autism assessment includes developmental history, standardized testing (ADOS-2, ADI-R), cognitive assessment, and clinical observation.
Do you need to get re-diagnosed with autism when DSM criteria change? How Ontario handles older diagnoses, PDD-NOS, Asperger syndrome, and OAP eligibility under current DSM-5 criteria.
Commitment to Accuracy: Our data is verified against official government reports (FAO, MCCSS), peer-reviewed scientific literature, and accessible public records. Last updated: March 24, 2026.
Written by Spencer Carroll
Founder & Autism Advocate