[1] Univ Glasgow, Robertson Ctr Biostat & Clin Trials, Level 11,Boyd Orr Bldg,Univ Ave, Glasgow G12 8QQ, Lanark, Scotland
[2] Imperial Coll, London, England
[3] Univ Hosp Basel, Dept Cardiol, Basel, Switzerland
[4] Univ Hosp Basel, Cardiovasc Res Inst Basel, Basel, Switzerland