1. Children's Hospital; Helsinki University Hospital and University of Helsinki; Helsinki Finland
2. Stanford University School of Medicine, Cardiovascular Medicine; Stanford CA
3. Centre for Health and Social Economics; National Institute for Health and Welfare; Helsinki Finland
4. Information Services; National Institute for Health and Welfare; Helsinki Finland
5. Statistics Finland; Helsinki Finland
6. Department of Chronic Disease Prevention; National Institute for Health and Welfare; Helsinki Finland
7. Department of Obstetrics and Gynecology; MRC Oulu; Oulu University Hospital and University of Oulu; Oulu Finland