[1] Univ Cologne, Univ Hosp Cologne, Fac Med, Inst Hlth Econ & Clin Epidemiol IGKE, D-50923 Cologne, Germany
[2] Kidney Ctr Wiesbaden, D-65189 Wiesbaden, Germany
[3] Rhineland State Council, Inst Hlth Care Res, D-51109 Cologne, Germany
[4] Univ Cologne, Fac Human Sci & Med, Inst Med Sociol, Hlth Serv Res & Rehabil Sci IMVR, D-50923 Cologne, Germany
[5] Univ Bern, Univ Hosp, Dept Emergency Med, Inselspital, CH-3012 Bern, Switzerland