Autism spectrum disorder (ASD) is an important cause of developmental disability worldwide. According to the study titled Prevalence of Neurodevelopmental disorders in children aged 2-9 years, there has been a 178 per cent rise in the prevalence of autism in the past 20 years. In India, every one in 100 children below the age of 10 has autism. The findings of the research highlights an urgent need for better diagnostic tools, personalised care and management of ASD.India is a populous country of nearly 1.3 billion people with kids below 15 years constituting nearly one-third of the population. It has been estimated that more than two million people might be affected with ASD in India. Most of the reported studies on ASD are based upon hospital-based data and thus lack concrete information on the prevalence estimates of this disorder in India. There are only a few studies focusing on its prevalence in the community settings. Furthermore, lack of uniform application of fully validated and translated autism diagnostic tools makes it difficult to estimate the exact prevalence of ASD. There is also under-recognition of the disorder due to a delay in the diagnosis of ASD at a young age.Narendra Arora, who led a study on autism spectrum disorder in Indian children at the INCLEN Trust International, fanned out to five regions of India that differ economically and culturally, and went door to door to recruit children for evaluation. They recruited 20 children from each of 25 or 50 villages and municipal wards in each region. Altogether, they assessed 2,057 children aged two through five years and 1,907 children aged six through nine. The most common conditions the team identified are hearing impairments and intellectual disability. Nearly one in five children who has one neurodevelopmental condition also has a second condition.Arora and his colleagues had the children assessed at nearby hospitals for vision and hearing problems, epilepsy, neuromotor conditions such as cerebral palsy, speech problems, autism and intellectual disability. Children aged six through nine were also tested for attention deficit hyperactivity disorder and learning disorders. The team diagnosed 44 children with autism, using a free test called the INDT-ASD they had developed for use in low-resource countries.About one in six families with children declined to participate, perhaps because of stigma associated with the conditions, Arora says. Whats more, a smaller proportion of children in the study have developmental delays caused by poor nutrition than the national average, likely because the sample is not representative of the whole population. The study identified risk factors for developmental problems, such as home birth, serious childhood illnesses and low birth weight that the government can address.