1. Scientific Institute of Public Health, Operational Directorate Public Health & Surveillance, Brussels, Belgium.
2. End-of-Life Care Research Group, Vrije Universiteit Brussel, Brussels, Belgium.
3. Department of General Practice, Vrije Universiteit Brussel, Brussels, Belgium.
4. EMGO Institute for Health and Care Research, VU University Medical Centre, Amsterdam, The Netherlands.
5. Department of Public and Occupational Health, EMGO Institute for Health and Care Research, VU University Medical Centre, Amsterdam, The Netherlands.