Eirini Karyotaki1, Wouter van Ballegooijen2. 1. Department of Global Health and Social Medicine, Harvard Medical School, Boston, MA 02115 USA; Department of Clinical, Neuro- and Development Psychology, Section Clinical Psychology, Vrije Universiteit, Amsterdam, Amsterdam, Netherlands; Amsterdam Public Health Research Institute, Faculty of Behavioural and Movement Sciences, Vrije Universiteit, Amsterdam, Amsterdam, Netherlands. Electronic address: eirini_karyotaki@hms.harvard.edu. 2. Department of Clinical, Neuro- and Development Psychology, Section Clinical Psychology, Vrije Universiteit, Amsterdam, Amsterdam, Netherlands; Amsterdam Public Health Research Institute, Faculty of Behavioural and Movement Sciences, Vrije Universiteit, Amsterdam, Amsterdam, Netherlands; Department of Psychiatry, Amsterdam UMC, Vrije Universiteit, Amsterdam, Amsterdam, Netherlands; GGZ in Geest Specialized Mental Health Care, Amsterdam, Netherlands.