1. Institute for Applied Epistemology and Medical Methodology, University of Witten-Herdecke, Zechenweg 6, 79111 Freiburg, Germany
2. Paediatric Practice, Quellengasse 42, 8010 Graz, Austria
3. Integrative Medicine Institute, Overton Street, Portland, OR 97210, USA
4. University of Applied Sciences Leiden, Zernikedreef 11, 2333 CK Leiden, The Netherlands
5. Louis Bolk Instituut, Hoofdstraat 24, 3972 LA Driebergen-Rijsenburg, The Netherlands