1 Department of General Practice & Elderly Care Medicine, University Medical Centre Groningen, University of Groningen, Groningen, the Netherlands.
2 Department of Sociology and Interuniversity Centre for Social Science Theory and Methodology (ICS), University of Groningen, Groningen, the Netherlands.
3 Accare, University Centre for Child and Adolescent Psychiatry, Groningen, the Netherlands.
4 WHO Athens Office for Quality of Care and Patient Safety, Athens, Greece.
5 Universitat Witten/Herdecke, Witten, Germany.
6 Public Health Scotland, Edinburgh, Scotland.
7 WHO Country Office, Bucharest, Romania.
8 WHO, Department for Health System Governance and Financing, Geneva, Switzerland.
9 Department of Women's and Children's Health, King's College London, London, England.