1. Department of Health Sciences Faculty of Science, Vrije Universiteit Amsterdam The Netherlands
2. Nivel Netherlands Institute for Health Services Research Utrecht The Netherlands
3. Amsterdam UMC Amsterdam Public Health Research Institute Amsterdam The Netherlands
4. Department of Disease Control London School of Hygiene and Tropical Medicine London UK
5. Center for Health Services Research in Primary Care Durham Veterans Affairs Medical Center Durham North Carolina USA
6. Department of Population Health Sciences Duke University Durham North Carolina USA
7. Vrije Universiteit University Library Amsterdam The Netherlands
8. Department of Clinical Pharmacology and Pharmacy Amsterdam UMC Amsterdam The Netherlands
9. Department of PharmacoTherapy, Epidemiology & Economics (PTEE), Faculty of Mathematics and Natural Sciences, Groningen Research Institute of Pharmacy University of Groningen Groningen the Netherlands