[1] Univ Hosp Essen, Dept Integrat Med, Essen, Germany
[2] Charite Univ Med Ctr, Inst Social Med Epidemiol & Hlth Econ, Konigstr 63, D-14109 Berlin, Germany
[3] Immanuel Hosp Berlin, Konigstr 63, Berlin, Germany
[4] Immanuel Hosp Berlin, Dept Internal & Complementary Med, Berlin, Germany
[5] Karl & Veronica Carstens Fdn, Essen, Germany