1. Department of Cardiology, Rigshospitalet, Copenhagen University Hospital , Blegdamsvej 9, 2100 Copenhagen , Denmark
2. Danish Center for Clinical Health Services Research, Department of Clinical Medicine, Aalborg University , 9220 Aalborg , Denmark
3. Department of Cardiology, Copenhagen University Hospital Herlev and Gentofte , 2900 Hellerup , Denmark
4. Department of Clinical Epidemiology, Aarhus University Hospital , 8200 Aarhus , Denmark
5. Department of Cardiology, Aarhus University Hospital , 8200 Aarhus , Denmark
6. Department of Cardiology, Aalborg University Hospital , 9000 Aalborg , Denmark
7. Unit of Clinical Biostatistics and Epidemiology, Aalborg University Hospital , 9000 Aalborg , Denmark
8. Department of Cardiology, Odense University Hospital , 5000 Odense , Denmark