estimates of autism prevalence in the USA 2014 are 2.24% or 1 in 45

In the USA, another report shows autism rates of 2.24% or 1 in 45: see http://www.cdc.gov/nchs/data/nhsr/nhsr08...

These latest values bring the results of three national surveys of autism prevalence into alignment. In addition to the NHIS, the US also identifies autism prevalence values from the Autism and Developmental Disabilities Monitoring Network (ADDM) and the National Survey of Children’s Health (NSCH). The most recent results from the NSCH put autism prevalence at 1 in 50 children. This latest NHIS prevalence of 1 in 45 converges on that finding, and the agreement among the studies strengthens their conclusions.

see http://www.forbes.com/sites/emilywilling...

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The 2.24% prevalence also is remarkably close to the 2.64% reported in a thorough investigation of autism prevalence in the South Korean population. Lipkin sees that similarity as pointing to the universality of autism. “This is not a function of professional practice, cultural differences in parenting, or differing parental perspectives on their children,” he said.

The report suggests that if you ask parents/families whether they have been told their child has autism or an autism spectrum disorder, then it matters how you ask the question. After the question was changed in the 2014 survey, the results showed that a similar number of children had some form of developmental delay but many more of them has some type of ASD.

See also:

Recent data on the prevalence of autism in Australia is available at Autism prevalence in Australia 2015.