[1] Duke Univ, Med Ctr, Duke Clin Res Inst, Durham, NC 27710 USA
[2] Univ Colorado Denver, Div Cardiol, Aurora, CO USA
[3] London Sch Hyg & Trop Med, London WC1, England
[4] Univ Glasgow, Glasgow, Lanark, Scotland
[5] Brigham & Womens Hosp, Boston, MA 02115 USA
[6] Sahlgrens Univ Hosp, Dept Med, Gothenburg, Sweden
[7] McMaster Univ, Hamilton, ON, Canada
[8] AstraZeneca LP, Wilmington, DE USA