1. Department of Palliative Medicine, University Hospital Cologne, Cologne, Germany
2. Institute for Medical Sociology, Health Services Research and Rehabilitation Science (IMHR), Cologne, Germany
3. Department of Palliative Medicine, University Hospital Cologne, Cologne, Germany; Centre for Integrated Oncology Cologne/Bonn (CIO), Germany; Clinical Trials Centre Cologne, Cologne, Germany (ZKS)