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We developed and tested the Indian Autism Screening Questionnaire (IASQ), which was reported to be reliable and valid as compared to the Indian Scale for Assessment of Autism (ISAA) and the Childhood Autism Rating Scale -2 (CARS2). The present study describes the feasibility, acceptability, sociodemographic and developmental details of IASQ study participants in 5 settings- a psychiatry outpatients’ clinic (n = 145), a specialised paediatric clinic (n = 24), a speciality disability centre (n = 174), a primary school (n = 41) and a government housing colony (n = 255). The IASQ could be easily administered and understood. Consistent with prior reports, the male-female ratio of participants with autism was 3.8:1. Developmental complications were reported more frequently in clinical settings, while delivery by Caesarean section was commoner among community-dwelling higher socioeconomic status mothers (53% of the officers’ sample). Mothers of participants with autism more frequently reported Caesarean section birth for the proband (χ2 = 41.61, p < .0001) and prenatal and postnatal complications. Binary logistic regression confirmed that perinatal complications in the mother and father’s (older) age at birth of the participant were associated with autism. The IASQ is a reliable, practical tool for screening for autism in clinical and non-clinical settings in India.