[1] Univ Oslo, Aker Hosp, Dept Cardiol, N-0514 Oslo, Norway
[2] Univ Gothenburg, Sahlgrenska Hosp, Gothenburg, Sweden
[3] Arhus Univ Hosp, Aarhus, Denmark
[4] Helsinki Univ Hosp, FIN-00170 Helsinki, Finland
[5] Landspitalinn Univ Hosp, Reykjavik, Iceland
[6] MSD Scandinavia, Stockholm, Sweden
[7] Univ Oslo, Ulleval Hosp, N-0316 Oslo, Norway
[8] Merck Res Labs, Rahway, NJ USA
[9] Odense Univ Hosp, DK-5000 Odense, Denmark
[10] Univ Oslo, Natl Hosp, Oslo, Norway
[11] Linkoping Univ Hosp, S-58185 Linkoping, Sweden
[12] Kuopio Univ Hosp, SF-70210 Kuopio, Finland
[13] Nord Sch Publ Hlth, Gothenburg, Sweden