European Organisation for Research and Treatment of Cancer (EORTC), European Organisation for Research and Treatment of Cancer (EORTC), University of Amsterdam - University Medical Center, Karolinska Institutet, University of Copenhagen, Faculty of Health and Medical Sciences, Department of Public Health, University Hospital Magdeburg, Adelphi Values, Patient-Centered Outcomes, University of Leeds, Leiden University - Leiden University Medical Center (LUMC), Medical University of Graz, University Medical Center Mainz, Maria Sklodowska-Curie National Research Institute of Oncology, Innsbruck Institute of Patient-centered Outcome Research (IIPCOR), University of Southampton, Princess Máxima Center for Pediatric Oncology, University Hospital Regensburg - Center for Clinical Studies, University of Amsterdam - Amsterdam University Medical Centers, Leiden University - Leiden University Medical Center (LUMC), The University of Sydney - School of Psychology and European Organisation for Research and Treatment of Cancer (EORTC)