[1] Aarhus Univ, Dept Biostat, DK-8000 Aarhus C, Denmark
[2] Roskilde Cty Psychiat Hosp Fjorden, Dept Clin Chem, Roskilde, Denmark
[3] Aarhus Univ Hosp, Skejby Hosp, Dept Cardiothorac & Vasc Surg, Aarhus, Denmark
[4] Univ Aarhus, Inst Expt Clin Res, DK-8000 Aarhus, Denmark