Ethnic labels

With World Autism Awareness Day just behind us, it seems fitting to me to ask: is autism more common among children of some ethnicities than in others?

Last fall, I wrote about a mysterious cluster of autism among Somali children in Minnesota. At the time, the Minneapolis school system reported that although Somalis make up just 6 percent of the city’s public school population, they comprise 17 percent of the special education students labeled ‘autistic’.

Public health clusters are usually suspect, but in a report released last week, the Minnesota Health Department and the Centers for Disease Control and Prevention confirmed that, among 3- and 4-year-old children, those of Somali origin are two to seven times more likely to be placed in preschool programs for autism. The report also found other ethnic trends in these classes: just two Asians and one Native American between 2005 and 2007.

The report is unusual, sure, but it is hardly solid evidence. For one thing, the autism diagnoses weren’t standardized: some of the children received their diagnosis from school evaluators, others from medical doctors.

Second, there are any number of social factors that could explain the numbers. For instance, Asian and Native American children with autism may be more likely to go to private schools instead of public ones. Because some Somali parents have been outspoken about the disorder’s prevalence in their community, school evaluators may also be more likely to give a Somali child a diagnosis of autism.

The report made no attempt to explain why autism numbers may be higher in Somali communities. Some scientists claim that the disorder may result from a deficiency of Vitamin D, but this, too, is far from proven.

What would convince me are comprehensive surveys of autism prevalence in ethnic communities across the world — something that, so far at least, is sorely lacking.