1. Department of Anaesthesiology I, Witten/Herdecke University, Witten, Germany; Helios Clinic Wuppertal, Germany.
2. Palliative Medicine, Centre Hospitalier Universitaire Vaudois (CHUV), University of Lausanne, Switzerland.
3. Institute of Statistics, University of Munich, Munich, Germany.
4. Witten/Herdecke University, Germany.
5. Interdisciplinary Center for Palliative Medicine, University Hospital Munich, Munich, Germany.
6. Institute of Ethics, History and Theory of Medicine, University of Munich, Munich, Germany.