1. Fernie JA Penning-van Beest PhD, Research Associate, PHARMO Institute, Utrecht, Netherlands
2. Miriam CJM Sturkenboom PhD PharmD MsC, Associate Professor of Pharmacoepidemiology, IPCI, Department of Medical Informatics, Erasmus University Medical Center, Rotterdam, Netherlands
3. Bart LH Bemelmans MD PhD, Urologist, Department of Urology, University Medical Center, Nijmegen, Netherlands
4. Ron MC Herings PhD, Associate Professor of Pharmacoepidemiology, Utrecht University; Director, PHARMO Institute, Utrecht Reprints not available from authors