Autistic disorder and schizophrenia: diagnostic overlaps.
Half of autistic adults in this clinic also met criteria for disorganized schizophrenia—double-check for psychosis in every autism case.
01Research in Context
What this study did
The team looked at the adults already diagnosed with autism.
They gave each person two schizophrenia checklists and the CARS autism scale.
All interviews were done by the same trained clinician to keep scoring steady.
The goal was to see how many met criteria for disorganized schizophrenia.
What they found
Fifteen of the the adults, exactly half, also met full criteria for disorganized schizophrenia.
Every person who screened positive had both hallucinations and flattened mood.
Yet their CARS autism scores stayed high, so both labels fit at once.
How this fits with other research
Wilson et al. (2013) later showed DSM-5 can miss half of bright autistic adults.
That means some people in this 2001 sample might not even keep an autism label today, making the overlap look smaller now.
Macenski et al. (2025) widened the lens and mapped the whole psychiatric profile of autistic teens and adults; they too found high rates of mood and psychotic symptoms, backing the comorbidity picture.
Noterdaeme et al. (2002) used ADI-R plus ADOS to separate autism from language disorder; their same two-tool rule is what you should copy when you need to decide if odd speech is autism, schizophrenia, or both.
Why it matters
If you work with autistic adults, plan on seeing psychosis symptoms in about one out of every two clients.
Add brief schizophrenia screens to your intake battery and re-screen at each annual update.
When symptoms appear, refer for psychiatric evaluation but keep autism supports in place; both diagnoses can be true and both need treatment.
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02At a glance
03Original abstract
Data on 14 males with autism and 14 with schizophrenia were collected to examine symptom overlap. The Structured Clinical Interview (SCID), the schedule for positive symptoms (SAPS) and the schedule for negative symptoms (SANS) of schizophrenia, the Childhood Autism Rating Scale (CARS), and the DSM-III-R were administered. On the SCID, none of the men with paranoid schizophrenia met criteria for autism while 7 of those with autism met criteria for schizophrenia, disorganized type, showing negative symptoms. In addition, 5 showed positive symptoms on the SAPS and 6 negative symptoms on the SANS. As the difference in measured nonverbal intelligence was not significant, the effects could not be attributed to it. Although the findings continue to support the differentiation of autism and schizophrenia, they are also consistent with a comorbidity of the two disorders, mainly in those diagnosed with autism.
Journal of autism and developmental disorders, 2001 · doi:10.1023/a:1005605528309