1. Department of Medical Microbiology, University Hospital Maastricht, Maastricht, The Netherlands
2. Department of Medical Microbiology and Infectious Diseases, Erasmus Medical Centre, Rotterdam, The Netherlands
3. Scientific Institute of Dutch Pharmacists, The Hague, The Netherlands, and Department of Clinical Pharmacy, University Medical Centre St. Radboud, Nijmegen, The Netherlands
4. Department of Medical Microbiology, University Hospital Groningen, Groningen, The Netherlands