1. University of Groningen; University Medical Center Groningen; Department of General Practice; Groningen The Netherlands
2. University of Groningen; University Medical Center Groningen; Department of Medical Oncology; Groningen The Netherlands
3. University of Groningen; University Medical Center Groningen; Department of Abdominal Surgery; Groningen The Netherlands
4. University of Groningen; University Medical Center Groningen; Department of Pulmonary Diseases; Groningen The Netherlands
5. University of Groningen; University Medical Center Groningen; Department of Radiation Oncology; Groningen The Netherlands