| has gloss | eng: The epidemiology of autism is the study of factors affecting autism spectrum disorders (ASD). Most recent reviews of epidemiology estimate a prevalence of one to two cases per 1,000 people for autism, and about six per 1,000 for ASD; Autism is largely inherited, although the genetics of autism are complex and it is generally unclear which genes are responsible. Although a link between autism and environmental exposures is plausible, little evidence exists to support associations with specific environmental exposures. Other proposed causes, such as childhood vaccines, are controversial and the vaccine hypotheses lack convincing scientific evidence. *The incidence rate of a condition is the rate at which new cases occurred per person-year, for example, "2 new cases per 1,000 person-years". *The cumulative incidence is the proportion of a population that became new cases within a specified time period, for example, "1.5 per 1,000 people became new cases during 2006". |
