1Department of Medical Oncology, University Hospital Basel, Basel, Switzerland
2Basel Institute for Clinical Epidemiology and Biostatistics, Department of Clinical Research, University Hospital Basel, University of Basel, Basel, Switzerland
3Department of Health Research Methods, Evidence and Impact, McMaster University, Hamilton, Ontario, Canada
4Department of Oncology and Hematology, Kantonales Spital Grabs, Grabs, Switzerland
5Department of Oncology and Hematology, Kantonsspital St. Gallen, Sankt Gallen, Switzerland
6University Medical Library, University of Basel, Basel, Switzerland
7Department of Medical Oncology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
8Department of Hematology/Oncology and Palliative Care, Klinikum Stuttgart Katharinenhospital, Stuttgart, Germany