[1] Stanford Univ, Stanford, CA USA
[2] Stanford Univ, Sch Med, Dept Anesthesiol Perioperat & Pain Med, Dept Epidemiol & Populat Hlth, Stanford, CA USA
[3] Brigham & Womens Hosp, Boston, MA USA
[4] Harvard Med Sch, Boston, MA USA
[5] Harvard Univ, Cambridge, MA USA
[6] Brigham & Womens Hosp, Div Pharmacoepidemiol & Pharmacoecon, Dept Med, Boston, MA USA
[7] Harvard Med Sch, Brigham & Womens Hosp, Boston, MA USA