[1] Univ Hosp Cologne AoR, Inst Hlth Econ & Clin Epidemiol, D-50935 Cologne, Germany
[2] Fed Joint Comm G BA, D-10623 Berlin, Germany
[3] Univ Witten Herdecke, Fac Hlth Sci, Gerhard Kienle Inst Med Theory Integrat & Anthrop, Ctr Integrat Med, D-58313 Herdecke, Germany