1. Department of Health; Functional Capacity and Welfare; National Institute for Health and Welfare; Turku and Helsinki; Finland
2. Tampere School of Public Health; University of Tampere; Tampere; Finland
3. Gerontology Research Centre; University of Jyväskylä; Jyväskylä; Finland
4. Department of Chronic Disease Prevention; National Institute for Health and Welfare; Turku; Finland