Assessment & Research

Prevalence and correlates of autism in a state psychiatric hospital.

Mandell et al. (2012) · Autism : the international journal of research and practice 2012
★ The Verdict

One in ten adult psychiatric inpatients has undiagnosed ASD—use SRS ≥84 plus early-onset history and substance-use notes to spot them.

✓ Read this if BCBAs doing intake or behavior planning on adult mental-health units.
✗ Skip if Early-intervention clinicians who only serve preschoolers.

01Research in Context

01

What this study did

Staff screened every adult in one state psychiatric hospital. They gave each patient the Social Responsiveness Scale. They also checked age of first symptoms and any drug or alcohol history.

The goal was to see how many inpatients had undiagnosed autism.

02

What they found

One in ten patients met ASD criteria. A cut-off of 84 on the SRS plus early onset and substance-use history caught most cases.

The simple combo worked better than the test alone.

03

How this fits with other research

Ressel et al. (2020) pooled 26 studies and found up to one-third of adults with ASD also misuse substances. Their review supports using drug history as a red flag.

Ellingsen et al. (2014) looked at outpatients and showed 57% of adults already diagnosed with ASD had another mental illness. Together the papers say: expect heavy overlap between ASD and psych disorders in any clinic.

Whaling et al. (2025) seems to disagree. They found autistic youth had lower drug-use rates than peers. The gap closes once you note age and setting: teens in the community differ from adults locked on a ward.

04

Why it matters

If you work with adult psychiatric patients, add the SRS to your intake pack. Score 84 or higher plus early social delays and any drug history should trigger a full autism evaluation. Catching missed ASD can explain challenging behavior and guide safer, quieter care plans.

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Add the SRS to your adult intake forms and flag scores ≥84 for autism follow-up.

02At a glance

Intervention
not applicable
Design
other
Sample size
141
Population
mixed clinical
Finding
positive

03Original abstract

This study estimated the ASD prevalence in a psychiatric hospital and evaluated the Social Responsiveness Scale (SRS) combined with other information for differential diagnosis. Chart review, SRS and clinical interviews were collected for 141 patients at one hospital. Diagnosis was determined at case conference. Receiver operating characteristic (ROC) curves were used to evaluate the SRS as a screening instrument. Chi-squared Automatic Interaction Detector (CHAID) analysis estimated the role of other variables, in combination with the SRS, in separating cases and non-cases. Ten percent of the sample had ASD. More than other patients, their onset was prior to 12 years of age, they had gait problems and intellectual disability, and were less likely to have a history of criminal involvement or substance abuse. Sensitivity (0.86) and specificity (0.60) of the SRS were maximized at a score of 84. Adding age of onset < 12 years and cigarette use among those with SRS <80 increased sensitivity to 1.00 without lowering specificity. Adding a history substance abuse among those with SRS >80 increased specificity to 0.90 but dropped sensitivity to 0.79. Undiagnosed ASD may be common in psychiatric hospitals. The SRS, combined with other information, may discriminate well between ASD and other disorders.

Autism : the international journal of research and practice, 2012 · doi:10.1177/1362361311412058