ADOS-2 Classification in a Psychiatric Population

Background: the Autism Diagnostic Observation Schedule, Second Edition (ADOS-2), is considered a "gold-standard" instrument for diagnosing autism spectrum disorder (ASD) in adults. Despite good sensitivity and specificity of the ADOS-2 are demonstrated in research and clinical settings with highly trained examiners, little is known about the accuracy of the diagnostic classification with psychiatric populations.

Objectives: to evaluate the accuracy of the ADOS-2 diagnostic classification in an acute psychiatric population.

Methods: we evaluated diagnostic classification of the first 36 individuals admitted to the inpatient unit with a possible ASD diagnosis. Reasons for admission included anxiety, depression, conduct disorder, oppositional defiant disorder, self-injurious behavior, and suicidal ideation.

Results: 8 out of a total of 36 individuals with ASD did not meet diagnostic criteria for classification in the ADOS-2. 8 out of a total of 36 individuals with Non Spectrum diagnosis met diagnostic criteria for classification in the ADOS-2. Sensitivity and specificity were both at 77% with 20 individual classified correctly (55%) and 16 individuals classified incorrectly (44%).

Conclusions: results indicate that the ADOS-2 diagnostic classification in patients admitted to a psychiatric unit should be interpreted carefully given the number of individuals classified incorrectly by the instrument.