Diagnostic Validity of the Persian version of 3rd edition of the Gilliam Autism Rating Scale (GARS-3)

Autism spectrum disorder (ASD) is a prevalent neurodevelopmental disorder, and early diagnosis is crucial for effective interventions. The Gilliam Autism Rating Scale (GARS-3) is a widely used tool for diagnosing ASD.

This descriptive research aimed to validate the Persian version of GARS-3. The sample consisted of 318 individuals aged 3 to 22 years with ASD, as well as normal, mentally retarded, and deaf individuals. Purposeful sampling was used to select the participants.

The results indicated that the Persian version of GARS-3 has good diagnostic and discriminative ability between individuals with ASD and those without (p < 0.05).

The study recommends using GARS-3 for screening ASD in Iranian children, emphasizing the importance of using DSM-5 diagnostic criteria alongside the scale’s desirable psychometric properties.