1. The Research Department for Health and Morbidity in the Population, National Institute of Public Health, University of Southern Denmark, Studiestræde 6, DK-1455 Copenhagen K, Denmark
2. Department of Cardiology, Herlev-Gentofte University Hospitals, Gentofte Hospitalsvej 1, DK-2900 Hellerup, Denmark
3. The National Knowledge Centre for Rehabilitation and Palliative Care, Vestergade 17, DK-5800 Nyborg, Denmark