Evaluating the effectiveness of Picture Exchange Communication System (PECS) on the receptive and expressive language components of children with autism spectrum disorder

The purpose of this research is to investigate the effectiveness of the picture exchange communication system (PECS) on the receptive and expressive language components of children with autism spectrum disorder. The method of this research is practical in terms of purpose and in terms of data collection, it is an experiment with AB single-subject design. The statistical population of the research consists of all children with autism spectrum disorder with average functioning of 6 to 8 years old who were studying in the special schools of Mashhad in the academic year 1401-1402. The sample of this research, which was obtained by the purposeful sampling method, consists of 5 children with autism spectrum disorder who were definitively diagnosed with autism spectrum disorder using the ADOS test. In order to collect data, expressive and receptive language tests of Nyusha Development Test have been used. The findings indicate that the mean verbal and receptive language scores of 6 to 8-year-old children with autism spectrum disorder have increased in the first post-test compared to the baseline. This increasing trend has continued in the process of implementing the training program of the communication system based on image exchange.