Autistic Disorder: A 20 Year Chronicle.

The team tracked 187 people diagnosed with Autistic Disorder in the late 1990s. They checked living situation, school, and work status twenty years later. No treatment was tested; this was a straight-up long-term picture.

Almost everyone—99 out of every 100—still needed family or group-home support. Only about one in twenty-five had any college experience. Independence and higher education were rare in this cohort.

McDonald (2012) looks at first like the opposite story: one in five cognitively able kids lost the autism label after just three years. The gap is IQ. That study only included children with scores of 70 and up; Cindy et al. drew from the full range seen in the 1990s, so severe intellectual disability pulls the average down.

Harstad et al. (2026) adds middle ground. By elementary school, about one third of toddlers no longer meet ASD criteria, yet many still need services for ADHD, language delay, or ID. It shows diagnostic change is possible, but support needs often remain.

Emerson et al. (2007) claims every child in a small parent-training program left the spectrum after thirty months. The sample was tiny, had no control group, and likely started with milder profiles. Cindy’s much larger, unselected cohort gives a sobering counter-weight.

For BCBAs, the takeaway is to plan early for lifelong adaptive skills. Use the Vineland alongside the ADOS to spot daily-living gaps while clients are still in school. Push for robust transition goals—household routines, money use, community mobility—because cognitive scores alone do not predict who will live independently.