[1] Univ Cologne, Fac Med, Dept Palliat Med, Cologne, Germany
[2] Univ Cologne, Univ Hosp, Cologne, Germany
[3] Univ Educ Heidelberg, Fac Educ & Social Sci, Dept Educ Sci, Heidelberg, Germany
[4] Univ Cologne, Fac Med, Clin Trials Ctr ZKS, Cologne, Germany
[5] Univ Cologne, Fac Med, Ctr Hlth Serv Res, Cologne, Germany
[6] Univ Cologne, Fac Med, Ctr Integrated Oncol Aachen Bonn Cologne Dusseldo, Cologne, Germany