Assessment of the relationship between diagnoses of ASD and caregiver symptom endorsement in adults diagnosed with intellectual disability.
Zero in on socialization items when using caregiver report to spot ASD in adults with severe ID.
01Research in Context
What this study did
Matson et al. (2013) asked caregivers of adults with intellectual disability to fill out the ASD-DA checklist.
Some adults had both ID and autism. Others had ID only.
The team wanted to know if caregiver answers could tell the two groups apart.
What they found
Caregiver scores on the socialization items were the clearest red flag.
When caregivers said the adult had few social interests or odd greetings, the adult usually had both ID and ASD.
Items about repetitive behavior helped less.
How this fits with other research
Mouga et al. (2015) saw the same pattern in kids. Even when IQ was matched, children with ASD scored lower on socialization than children with other delays.
Liu et al. (2026) updated the picture for toddlers. They showed ADOS-2 cut-offs need to be higher when the child also has global delay. Together the three studies say: check social skills first, then raise the bar when ID is present.
Žic Ralić et al. (2025) looked at social-emotional strengths instead of problems. Parents of kids with both ASD and ID rated the lowest skills, echoing the adult findings.
Why it matters
If you assess adults with profound ID, start with the socialization section of the ASD-DA. A low score is a quick screen for possible ASD. When the score is borderline, move to a gold-standard tool and keep the ID in mind. This one tweak can shorten your battery and get clients into the right services faster.
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02At a glance
03Original abstract
Individuals diagnosed with an intellectual disability (ID) share overlapping traits with those diagnosed with both ID and an Autism Spectrum Disorder (ASD). Therefore, the purpose of this study was to determine if caregivers' reports of symptoms of ASD are of value (i.e., when comparing them to clinical diagnoses of ASD) and to determine which symptoms of ASD best differentiate those with ASD from those with ID only. It was hypothesized that a subset of items would emerge using the Autism Spectrum Disorders-Diagnostic for Adults (ASD-DA) which would differentiate the two groups utilize in this study. One hundred eighty-six adults diagnosed with ID with and without diagnosis of ASD were assessed for core symptoms and other behavioral differences using the ASD-DA. Most of the individuals in the ID group (n = 93) and the ID plus ASD group (n = 93) were in the profound range of ID. The items which were most likely to distinguish individuals with ASD were in socialization domain. Furthermore, adults with ASD were more likely to be male and to be non-verbal.
Research in developmental disabilities, 2013 · doi:10.1016/j.ridd.2010.03.010