1. Department of Palliative Medicine, RWTH Aachen University, Aachen, Germany.
2. Care and Public Health Research Institute, University Maastricht, Maastricht, The Netherlands.
3. Department of Theology, RWTH Aachen University, Aachen, Germany.
4. Department of Palliative Medicine, University Hospital, Cologne, Germany.
5. Department of Palliative Medicine, University Hospital Göttingen, Göttingen, Germany.