[1] Harvard Univ, Sch Med, Brigham & Womens Hosp, TIMI Study Grp, Boston, MA 02115 USA
[2] Notttingham Clin Res Grp, Nottingham, England
[3] Monash Univ, Dept Epidemiol & Prevent Med, Melbourne, Vic 3168, Australia
[4] Harvard Univ, Sch Publ Hlth, Boston, MA 02115 USA
[5] Guys Hosp, London SE1 9RT, England