The study by researchers at Uppsala University and the Karolinska Institute in Solna found that when the children recover hormone levels return to normal.

“Our study is small, but the results are still so clear that we can reject all claims that the children simulated their symptoms. Altered levels of various so-called steroid hormones is not something that can be simulated,” said Jonas Bergquist, professor of neurochemistry at Uppsala University to the local UNT daily.

The more symptoms the children showed, the greater seemed to be hormonal changes, according to the new study.

The study has been published in the BMC Research Notes medical journal and included eleven children who were treated by the Sachsska Children’s Hospital in Solna, in collaboration with the child and adolescent psychiatric mobile team in Stockholm.

The issue of apathetic refugee children led to a fevered media debate in 2005/2006 after a report penned by child psychologist Marie Hessler which indicated that the children may have been faking the condition.

Several charities working within the field disputed the findings of the report, which was commissioned by Barbro Holmberg, the Social Democrat migration minister at the time.

Around 400 children, mostly from the former Soviet Union and Yugoslavia, were found to be suffering from the condition in 2005. The condition continues to affect refugee children seeking asylum in Sweden.

The underlying causes for the condition remain unclear but the symptoms result in children being confined to their beds for extended periods of time, showing no contact with the outside world and requiring tube feeding.