Denmark – Increase in autism cases linked to changes in diagnostic criteria and reporting methods

Aarhus, Denmark — Researchers found that the drastic increase in autism cases in Denmark may have been due to the changes in the diagnostic criteria as well as the reporting methods used to record the number of cases.

A group of researchers, mainly from Aarhus University in Denmark, analyzed data they gathered from a population-based birth group of about 677,915 children. The children involved in the study were those who were born between January of 1980 and December of 1991.

According to the study, 3,956 of these children were diagnosed with Autism Spectrum Disorder (ASD). From that number, however, only 192 of the cases were reported before 1994. An additional 100 cases were observed during the years 1994-1995, while a surprisingly higher number of cases were reported after 1995– wherein about 3,664 new cases were added to the statistics.

According to the researchers they state that 60 per cent of the increase found in the prevalence of ASD in children born  1980 through 1991 can be explained due to the changes in diagnostic criteria that were introduced from 1994 as well as the collection of out patient data.

“The diagnostic change might have led to a gradual increase in prevalence caused by, for example, a growing awareness among clinicians of the ASD features after the change that could have gradually altered the clinical perception of ASD.”

The journal article can be found here

The original article on the Healio.Com website can be found here

Contributed by Althea Estrella Violeta