1. Department of Chronic Disease Prevention; National Institute for Health and Welfare; Helsinki Finland
2. Department of General Practice and Primary Health Care; University of Helsinki; Helsinki Finland
3. Vasa Central Hospital; Vasa Finland
4. Folkhälsan Research Centre; Helsingfors Universitet; Helsinki Finland
5. Unit of General Practice; Helsinki University Central Hospital; Helsinki Finland
6. Hospital for Children and Adolescents; Helsinki University Central Hospital and University of Helsinki; Helsinki Finland
7. Center for the Study of Human Health; Emory University; Atlanta GA USA
8. MRC Lifecourse Epidemiology Unit (University of Southampton); Southampton General Hospital; Southampton UK