1. Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands.
2. Health and Youth Care Inspectorate, Utrecht, The Netherlands.
3. Department of Medical Informatics, Erasmus Medical Center, Rotterdam, The Netherlands.
4. Department of Bioanalysis, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium.
5. PHARMO Institute, Utrecht, The Netherlands.
6. Haga Teaching Hospital, The Hague, The Netherlands.