[1] Res Inst Havelhohe FIH, D-14089 Berlin, Germany
[2] Community Hosp Havelhohe, Dept Internal Med, Berlin, Germany
[3] Charite, Inst Social Med Epidemiol & Hlth Econ, D-13353 Berlin, Germany
[4] Inst Integrat Med, Witten, Germany
[5] Inst Clin Res IKF, Berlin, Germany
[6] Hannover Med Sch, Clin Rehabilitat Med, Hannover, Germany
[7] Univ Tubingen, Ctr Res Med & Nat Sci, Tubingen, Germany