1 Department of Internal and Integrative Medicine, Kliniken Essen-Mitte, Faculty of Medicine, University of Duisburg-Essen, Essen, Germany.
2 Department of Psychology, University of Connecticut, Storrs, CT, USA.
3 Endeavour College of Natural Health, Brisbane, QLD, Australia; Australian Research Centre in Complementary and Integrative Medicine (ARCCIM), Faculty of Health, University of Technology Sydney, Sydney, NSW, Australia.
4 National Institute of Mental Health and Neurosciences, Bangalore, India.
5 School of Health Sciences and Social Work, University of Portsmouth, Portsmouth, UK.