1. Parnassia Psychiatric Institute, The Hague
2. Department of Psychiatry, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
3. Department of Psychiatry, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa
4. Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York, USA