1. Department of General Practice, Julius Center, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
2. Nivel (Netherlands Institute for Health Services Research), Utrecht, The Netherlands
3. Division of Family Medicine and Primary Care, Department of Neurobiology, Care Sciences and Society (NVS), Karolinska Institutet, Stockholm, Sweden
4. Department of Medical Sciences, Cardiovascular Epidemiology, Uppsala University, Uppsala, Sweden
5. Clinic of Social and Family Medicine, School of Medicine, University of Crete, Greece
6. Institute of General Practice, First Faculty of Medicine, Charles University, Prague, The Czech Republic
7. Research Unit of General Practice, Department of Public Health, University of Southern Denmark, Odense C, Denmark
8. Department of General Practice & Elderly Care Medicine, Amsterdam Public Health Research Institute, VU University Medical Center, Amsterdam, The Netherlands