Prevalence of autism spectrum disorders among children (1-10 years of age) - findings of a mid-term report from Northwest India

India is the second most populous country of the world. A large portion of the population of this country is below 20 years of age but still there is a paucity of information about the prevalence and incidence of many developmental disorders. This study was planned to estimate the prevalence of autism spectrum disorders (ASDs) in the selected areas (tribal, rural, and urban) of a northern state of India, Himachal Pradesh. A cross-sectional two-phase study was conducted covering all the children in the range of 1-10 years of age. Phase one included screening of all the children in the age group of 1-10 years, with the help of an indigenous assessment tool for autism. The sociodemographic profile of the participants was also recorded during phase one. Phase two involved the clinical evaluation of individuals who were suspected of autism on screening. The results show a prevalence rate of 0.9/1000. The highest prevalence rate was observed in the rural area. Socioeconomic status (SES) may be one of the fundamental indicators for ASDs in India.