Autism spectrum disorders (ASD) are a group of neurodevelopmental conditions characterized by social and communication deficits, stereotyped interests and repetitive behaviors . Approximately one in 68 children are identified with ASD according to estimates from Centers for Disease Control and Prevention (CDC)’s Autism and Developmental Disabilities Monitoring (ADDM) Network . Systematic reviews around the world estimated different prevalence
rates of ASD [3–6]. Williams et al. estimated global ASD prevalence of 20 per 10,000 with high degree of heterogeneity among studies. Elsabbagh et al. reported a global median ASD prevalence of 62 cases per 10,000 population which translates to one child out of 160. Baxter et al. estimated prevalence of 7.6 per 1000 or one in 132 persons worldwide. In Asia, Sun and Allison conducted a systematic review in six Asian countries that excluded South Asian countries revealed prevalence of ASD from 1980 to present was 14.8 per 10,000 .