[1] Acad Med Ctr Amsterdam, Dept Vasc Med, Amsterdam, Netherlands
[2] Univ Iowa, Dept Epidemiol, Iowa City, IA USA
[3] Univ Iowa, Dept Med, Iowa City, IA 52242 USA
[4] Univ Witwatersrand, Fac Hlth Sci, Dept Med, Johannesburg, South Africa
[5] Univ Montreal, Inst Rech Clin Montreal, Montreal, PQ, Canada
[6] Prince Alfred Hosp, Dept Clin Biochem, Camperdown, NSW, Australia
[7] Amgen Inc, Thousand Oaks, CA 91320 USA
[8] Jacksonville Ctr Clin Res, Jacksonville, FL USA