1. Finnish Institute of Occupational Health; Helsinki Finland
2. Department of Social and Environmental Health Research; London School of Hygiene and Tropical Medicine; London United Kingdom
3. Department of Epidemiology and Public Health; University College London Medical School; London United Kingdom
4. Department of Health, Functional Capacity and Welfare; National Institute for Health and Welfare; Helsinki Finland
5. Department of Public Health; University of Turku; Finland
6. Department of Society, Human Development, and Health; Harvard School of Public Health; Boston Massachusetts USA
7. Turku University Hospital; Turku Finland