[1] Univ Penn, Perelman Sch Med, Ctr Clin Epidemiol & Biostat, Dept Biostat & Epidemiol, Philadelphia, PA 19104 USA
[2] Univ Penn, Perelman Sch Med, Dept Med, Philadelphia, PA 19104 USA
[3] AstraZeneca Pharmaceut LP, Dept Global Epidemiol, Wilmington, DE USA
[4] Bristol Myers Squibb Co, Dept Global Pharmacovigilance & Epidemiol, Hopewell, NJ USA
[5] Univ Penn, Perelman Sch Med, Dept Dermatol, Philadelphia, PA 19104 USA
[6] HealthCore Inc, Dept Safety & Epidemiol, Wilmington, DE USA
[7] Med & Healthcare Prod Regulatory Agcy, Gen Practice Res Database, London, England
[8] Cegedim Strateg Data Med Res, Dept Med Res, London, England