Identification and educational placement of students with intellectual disability in Ontario, Canada.
Ontario schools are quietly dropping the mild-ID label and funneling developmental-disability students into separate classes more than ever.
01Research in Context
What this study did
Sturm et al. (2024) looked at every student record in Ontario, Canada. They tracked who got labeled with intellectual disability and where those kids went to school.
The team used province-wide education files. No new tests. They simply counted trends already in the system.
What they found
Schools are writing down "mild intellectual disability" less often each year. At the same time, kids listed with "developmental disability" land in separate classrooms far more than kids with mild ID.
The shift is big enough to see across the whole province.
How this fits with other research
Friman (2014) followed Ontario teens with mild ID after they left school. Those same students had poor jobs, little college, and weak life skills years later. The new numbers show schools are now dropping the mild-ID label even before graduation.
Leung et al. (2011) found about 1 in every 100 kids worldwide has ID. Ontario’s drop in mild-ID counts looks like an under-count, not a true fall in prevalence.
Dion et al. (2018) show that when kids with ID do enter other systems—child protection—they have extra-severe needs. Less school identification could mean those needs stay hidden longer.
Why it matters
If you write IEPs in Ontario, check your caseload against the province trend. A student who once would have been called mild ID may now have a different label—or none at all—yet still need the same supports. Track placement, not just diagnosis. Push for service minutes based on skill gaps, not on the mild-ID checkbox that is disappearing.
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02At a glance
03Original abstract
BACKGROUND: Little is known about the identification and educational placement of students considered to have intellectual disability in the Canadian context and, specifically, the province of Ontario. AIMS: The purpose of this study was to describe trends in the school-based identification of students with mild intellectual disability and developmental disability based on the Ontario criteria over a 14-year period, as well as current patterns characterizing classroom placement. METHODS: Using data provided by the Ontario Ministry of Education, a doubly multivariate analysis of variance and profile analysis were performed. RESULTS: Findings revealed a statistically significant decrease in the number of students identified with mild intellectual disability over time, and that students identified with developmental disability per the provincial criteria accessed their education in specialized settings at a significantly higher rate than their peers with mild intellectual disability. CONCLUSIONS: Reasons for differences in the identification and placement of the two groups of students are explored relative to the research context.
Research in developmental disabilities, 2024 · doi:10.1016/j.ridd.2024.104740