[1] Katholieke Univ Leuven, Dept Radiat Oncol & Palliat Med, Leuven, Belgium
[2] Univ Hosp Gasthuisberg, Dept Radiat Oncol & Palliat Med, Leuven, Belgium
[3] Univ Lancaster, Fac Hlth & Med, Int Observ End Life Care Div Hlth Res, Lancaster, England
[4] Univ Hosp Bonn, Dept Palliat Med, Bonn, Germany
[5] Radboud Univ Nijmegen Med Ctr, Anesthesiol Pain & Palliat Care, Nijmegen, Netherlands
[6] Univ Navarra, Inst Culture & Soc, Pamplona, Spain