ADOS-2 Module 4: Psychometric Properties and Diagnostic Performance at an Autism-specialized Clinic.
ADOS-2 Module 4 works well for cognitively able adults, yet women often score lower and match the ADI-R less, so gather more data before you decide.
01Research in Context
What this study did
Christiansen et al. (2025) checked how well the ADOS-2 Module 4 spots autism in adults who can think at average level or above.
They compared the test scores to the gold-standard ADI-R interview and looked for sex differences.
What they found
The new algorithm agreed strongly with the ADI-R for most adults.
Women, however, scored lower on the ADOS-2 and their scores matched the ADI-R less often.
How this fits with other research
McQuaid et al. (2024) show that adult autism subgroups stay stable for years and predict real-life outcomes, so accurate first labels matter.
Udhnani et al. (2025) warn that kids with ADHD can be mis-read by autism screens; Jens adds that adult women may also be missed.
Symons et al. (2005) found short IQ forms work fine in high-functioning clients, reminding us we can trim testing time once autism is confirmed.
Why it matters
If you test bright adults, ADOS-2 Module 4 is solid, but add extra data for women. Combine it with the ADI-R, parent reports, or direct observations before you rule autism in or out.
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Join Free →Score ADOS-2 Module 4 as usual, but if the client is female, bring in the ADI-R or extra informants before you close the case.
02At a glance
03Original abstract
PURPOSE: Psychometric properties and diagnostic performance of the ADOS-2 module 4 were evaluated with participants from an autism-specialized clinic. METHODS: The sample had 331 participants with 226 males and 70 females receiving an ASD diagnosis. The evaluation consisted of the following: (1) A replication of the Exploratory Factor Analysis (EFA) reported by Hus, V., & Lord, C. (2014). The Autism Diagnostic Observation Schedule, Module 4: Revised Algorithm and Standardized Severity Scores. Journal of Autism and Developmental Disorders, 44(8), 1996-2012. https://doi.org/10.1007/s10803014-2080-3 .). (2) Identification of ADOS-2 items best predicting clinical diagnosis using Recursive Feature Elimination (RFE) and comparison of these items to previous findings. (3) Receiver Operating Characteristic (ROC) curve analyses of the effects of age and IQ on diagnostic performance. (4) Comparisons of ADOS-2 revised algorithm scores between females and males and their association with ADI-R scores. RESULTS: The EFA item-to-factor allocation of the ADOS-2 revised algorithm was largely reproduced. When comparing the present RFE to previous RFE findings, the item Quality of Social Responses stood out. ROC curve analysis showed outstanding diagnostic performance for adults with IQ above 70 but for females, ADOS-2 revised algorithm scores were lowered, and, contrary to males, did not correlate with ADI-R scores. CONCLUSION: Reproducing the item-to-factor allocation and finding outstanding agreement with the diagnostic decision for adults with IQ > 70 showcase the strength of the ADOS-2 revised algorithm. Furthermore, by incorporating, into future revisions, the finding of inter-clinic importance of the item Quality of Social Responses, performance might be further enhanced. Lastly, though, that female scores were lowered and did not correlate with ADI-R indicate a weakness in the ADOS-2 when applied to the adult female population.
Journal of autism and developmental disorders, 2025 · doi:10.3389/fpsyt.2022.826043