1 Basel Pharmacoepidemiology Unit, Division of Clinical Pharmacy and Epidemiology, Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland.
2 Boston Collaborative Drug Surveillance Program, Lexington, MA.
3 Boston University School of Public Health, Boston, MA.
4 Division of Clinical Neurophysiology, Department of Neurology, University Hospital Basel, Basel, Switzerland.
5 Hospital Pharmacy, University Hospital Basel, Basel, Switzerland.