1. Department of Addictology, First Faculty of Medicine, Charles University in Prague and General Teaching Hospital in Prague, Prague, Czech Republic,
2. National Institute of Mental Health, Klecany, Czech Republic,
3. French Monitoring Centre for Drugs and Drug Addiction, Saint Denis La Plaine Cedex France, Ile-de-France, France,
4. Drugs Information and Monitoring System, Trimbos Institute, Utrecht, The Netherlands,
5. Public Health Institute, Liverpool John Moores University, Liverpool, UK, and
6. National Bureau for Drug Prevention – Ministry of Health, Warsaw, Poland