A study suggests childhood autism in the Netherlands is more common in a area with a high proportion of IT workers. The figures suggest there’s more to it than coincidence, though how correlation translates to causation is still open to question.

The key figures come from research by Simon Baron-Cohen (cousins, before you ask) of the UK’s autism research centre and Rosa Hoekstra of the Open University, reported in New Scientist.

After hearing anecdotal references to high levels of autism among the children of the city of Eindhoven’s, the pair compared child autism rates in Eindhoven, Haarlem and Utrect. One major difference between the three is that Eindhoven (pictured) is considered something of a tech hub in the country, with almost a third of jobs in the city relating to computing.

The research found that Eindhoven had 229 cases of autism-spectrum disorders per 10,000 children, compared with 84 in Haarlem and 57 in Utrecht. As a control they checked two other psychiatric conditions (ADHD and dyspraxia) and found no significant variations among the children of the different cities.

The next step in the research is to try to come up with an explanation. While the natural assumption is that people who thrive in computing jobs are genetically more likely to have children with autism, the researchers will be looking for other possibilities such as disparities in the way the condition is diagnosed or treated in the cities.

New Scientist noted a previous project in California that found reported cases of autism rose steadily between 1987 and 2007, far outpacing the state’s population growth, with the biggest rise coming in the South of the state where “Silicon Valley” lies. Two notable elements of that research was the discovery of a trend by which the proportion of autism sufferers in the state who also displayed mental retardation dropped dramatically, while the demographic breakdown switched from all ages being represented roughly equally, to a distinct pattern of the condition being more common among young children. Of course, that may be the result of greater efforts to diagnose the condition among children.