1. Department of Palliative Medicine, University Hospital, Cologne, Germany.
2. Institute for Medical Sociology, Health Services Research and Rehabilitation Science, University of Cologne, Cologne, Germany.
3. Center for Health Services Research Cologne, Cologne, Germany.
4. Division of Palliative Medicine, University Hospital, Erlangen, Germany.
5. Center for Integrated Oncology, Cologne/Bonn, Germany.
6. Center for Clinical Trials, University Hospital, Cologne, Germany.