Most of Increase in Autism Due to Changes in Diagnosing and Reporting


About 60% of the increase in the prevalence of autism spectrum disorders has been caused by broader diagnostic criteria and new reporting practices, according to a Danish study published in JAMA Pediatrics. Although the study was of Danish children, some of the findings would apply in the United States as well, a researcher not involved in the study told LiveScience.

“The percentage of children with autism worldwide has increased in recent years, but it’s not clear whether this rise is due mainly to changes in how doctors diagnose autism and report cases, or if there is some factor in children’s environment that is affecting autism rates,” reported LiveScience.

The researchers examined the records for nearly 678,000 children born between 1980 and 1991. “During this period, 3,956 of the children were diagnosed with autism, and most of these cases (95 percent) were reported after 1995,” reported LiveScience. “These changes in reporting practices include a 1994 change in the criteria used to diagnose autism, and also a 1995 change in the way autism cases are recorded in Denmark’s health system.”

(Abstract) Explaining the Increase in the Prevalence of Autism Spectrum DisordersThe Proportion Attributable to Changes in Reporting Practices (Hansen, Stefan N. et al. JAMA Pediatr. Published online November 03, 2014. doi: 10.1001/jamapediatrics.2014.1893)

Autism’s Rise: Researchers Look at Why Cases Are Increasing (LiveScience, November 3, 2014)


  1. I have an adult child “on the spectrum.” While his difficulties are not as bad as some, his issues are real and the diagnosis has given a name for something that he and our family have struggled with for two decades. I wonder if the number of diagnoses are going up in part because more women are using more meds and are exposed to more toxins during pregnancy??? I was given Phenergan for severe morning sickness for months during my pregnancy with him and I worry that this caused his extra difficulties…that said, there may be more diagnoses of autism as well…Big Pharma is always looking for a new market!

    BTW, we have found many very helpful environmental supports and have avoided meds for his struggles and ‘sensitivities’ for all these years…things are good, but I cannot deny that his difficulties are real…

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