1. 1 EMGO Institute for Health and Care Research, VU University Medical Center, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands
2. 2 Department of General Practice & Elderly Care Medicine, VU University Medical Center, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands
3. 3 Department of Public Health and Primary Care, Leiden University Medical Center, Hippocratespad 21, 2300 RC Leiden, The Netherlands
4. 4 Netherlands Institute for Health Services Research, Otterstraat 118–124, 3513 CR Utrecht, The Netherlands
5. 5 Dutch Institute for Rational Use of Medicine, Churchilllaan 11, 3527 GV Utrecht, The Netherlands
6. 6 Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Antonie van Leeuwenhoeklaan 9, 3721 MA Bilthoven, The Netherlands
7. 7 Department of Pharmacy, Radboud University Medical Center, Geert Grooteplein-Zuid 10, 6525 GA Nijmegen, The Netherlands
8. 8 Cecil G. Sheps Center for Health Services Research, University of North Carolina at Chapel Hill, 725 Martin Luther King Jr Blvd, Chapel Hill, NC 27599-7590, USA
9. 9 Department of Family Medicine, School of Medicine, University of North Carolina at Chapel Hill, 590 Manning Drive, Chapel Hill, NC 27599, USA
10. 10 School of Social Work, University of North Carolina at Chapel Hill, 325 Pittsboro St, Chapel Hill, NC 27599-3550, USA
11. 11 Department of Epidemiology and Biostatistics, VU University Medical Center, De Boelelaan 1118, 1081 HV Amsterdam, The Netherlands