1. Department of Palliative Medicine, University Hospital of Cologne, Cologne, Germany
2. Clinical Trials Center Cologne (ZKS), Medical Faculty, University of Cologne, Cologne, Germany
3. Center for Integrated Oncology (CIO Köln Bonn), University Hospital of Cologne, Cologne, Germany
4. Center for Health Services Research (ZVFK), Medical Faculty, University of Cologne, Germany