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In this study, we have examined the effectiveness of operant conditioning on the
development of linguistic skills in Persian children with autism. It was a quasiexperimental
study, and done by using pre- and post-tests. We randomly selected 40
children (6 girls and 34 boys, 5-10 years old) and divided them into experimental and
control groups comprising of 20 children each. We used the Autism Spectrum Screening
Questionnaire (ASSQ) to screen subjects and the Test of Language Development (TOLDP:
3) to measure their language skills. Both groups received grammatical comprehension
and grammatical completion subtests. Using the Applied Behavior Analysis (ABA)
method, the experimental group was then subjected to 48 one-hour intervention sessions
ran for 24 weeks. After the intervention, we ran a post-test in both experimental and
control groups. The data were analyzed using SPSS software. In the experimental group,
the mean score in the grammatical completion subtest had increased by 4.2, and in the
grammatical comprehension subset, the mean score had increased by 3.6. In contrast, in
the control group, the mean score of the grammatical completion and comprehension
subtests had increased by 0.25 and 0.3, respectively. The findings suggested that operant
conditioning had direct effects on the improvement of the 5-10 years old Persianspeaking
children with autism.