[1] Brigham & Womens Hosp, Div Pharmacoepidemiol & Pharmacoecon, Dept Med, Boston, MA 02115 USA
[2] Harvard Univ, Sch Med, Boston, MA USA
[3] Harvard Univ, Sch Publ Hlth, Dept Epidemiol, Boston, MA 02115 USA
[4] Brigham & Womens Hosp, Channing Div Network Med, Boston, MA 02115 USA
[5] Brigham & Womens Hosp, Clin Res Program, Dept Dermatol, Boston, MA 02115 USA
[6] Brigham & Womens Hosp, Dept Obstet Gynecol & Reprod Biol, Boston, MA 02115 USA
[7] Indiana Univ, Dept Epidemiol, Fairbanks Sch Publ Hlth, Simon Canc Ctr, Indianapolis, IN 46204 USA