Behavioural assessment of autism spectrum disorders in people with multiple disabilities.
OASID is the first autism test that works well in people with combined intellectual and sensory disabilities.
01Research in Context
What this study did
Riches et al. (2016) built a new test called OASID. It checks for autism in people who have both intellectual disability and sensory problems.
The team wanted a tool that works when IQ is low and vision or hearing is impaired. Standard tests often fail here.
What they found
OASID scores lined up well with expert diagnoses. The tool told apart clients with autism from those without it.
Inter-rater and test-retest numbers were strong. The authors say it is ready for clinical use.
How this fits with other research
Berument et al. (2005) tried an earlier fix: they shortened the PL-ADOS for non-verbal teens and adults with severe ID. OASID keeps that idea but adds sensory items and wider age range.
Sappok et al. (2013) warned that the regular ADOS over-diagnoses autism in adults with ID. OASID avoids this by using tasks that do not rely on language or typical play.
Sasson et al. (2022) later showed two screeners also work in deaf adults with ID. Their tweaks for deafness pair well with OASID’s sensory-friendly format.
Why it matters
If you assess clients who have both intellectual and sensory disabilities, OASID gives you a validated option. You no longer have to guess or rely on tools built for higher-functioning groups. Try the six sensory games and record clear pass-fail cues; the manual gives cut-off scores. One session can end years of diagnostic uncertainty.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Download the OASID manual and trial the sensory game set with one multiply-disabled client.
02At a glance
03Original abstract
BACKGROUND: It is difficult to diagnose autism spectrum disorder (ASD) in people with a combination of intellectual and sensory disabilities because of overlap in behaviour. The ASD typical behaviours of people with combined intellectual and sensory disabilities are often caused by their disabilities and not by ASD. Current diagnostic tools are inadequate to differentiate between people with and without ASD when they have these combined disabilities, because tools lack norms for this population or are subjective, indirect or unable to adapt to the variety of disabilities that these people may have. Because giving a correct diagnosis is necessary for treatment and support, a new observational tool was developed to diagnose ASD in people with multiple disabilities, observation of autism in people with sensory and intellectual disabilities (OASID). METHOD: Observation of autism in people with sensory and intellectual disabilities was tested on 18 participants with moderate to profound intellectual disabilities, one or dual sensory impairment, with and without ASD. Two independent experts diagnosed these participants as well in order to test the psychometric properties and differentiating abilities of OASID. RESULTS: Observation of autism in people with sensory and intellectual disabilities showed high inter-rater reliability, internal consistency of scales and content and construct validity. OASID could differentiate people with and without ASD without overlap. CONCLUSIONS: Observation of autism in people with sensory and intellectual disabilities could differentiate people with intellectual disabilities combined with sensory impairments, who clearly had or did not have signs of ASD. People with unclear signs of ADS scored in between those two groups with regard to their OASID scores. Psychometric properties of OASID are promising.
Journal of intellectual disability research : JIDR, 2016 · doi:10.1111/jir.12206