1. Institute of Public Health, Charité-Universitätsmedizin Berlin, Seestrasse 73, 13347 Berlin, Germany
2. Institute for Social Medicine, Epidemiology, and Health Economics, Charité-Universitätsmedizin Berlin, 10098 Berlin, Germany
3. Institute for Complementary and Integrative Medicine, University of Zurich and UniversityHospital Zurich, Rämistrasse 100, 8091 Zurich, Switzerland