[1] Brigham & Womens Hosp, Div Pharmacoepidemiol & Pharmacoecon, Boston, MA 02115 USA
[2] GlaxoSmithKline, Worldwide Epidemiol, Res Triangle Pk, NC USA
[3] Boston Univ, Sch Publ Hlth, Slone Epidemiol Ctr, Boston, MA USA
[4] Boston Univ, Sch Med, Slone Epidemiol Ctr, Boston, MA 02118 USA
[5] Merck & Co Inc, Global Ctr Sci Affairs, West Point, PA USA