Incidence was lower than for the non-immigrant population among immigrants from among others, Western European countries, Eastern Europe except Poland, the Balkans and Russia, the Philippines, China and North America. Incidence was also higher for persons with two immigrant parents for all countries of origin, including Nordic and Western European countries. When the data was corrected for the population group's age and gender structure (the most over-represented immigrant groups also have a considerable over-representation of young men), place of residence (rural–central) and employment situation, the over-representation was found to be significantly lower, especially for those groups which had the highest incidence in the uncorrected statistics.