1. Department for Psychiatry, Psychotherapy and Psychosomatics, Centre for Addictive Disorders; University Hospital of Psychiatry Zurich; Zurich Switzerland
2. Division of Addictive Disorders; University of Basel Psychiatric Hospital; Basel Switzerland
3. Swiss Research Institute for Public Health and Addiction; University of Zurich; Zurich Switzerland
4. Polyclinics for Heroin Prescription Lifeline/Crossline; City Medical Services; Zurich Switzerland
5. Arud Centres for Addiction Medicine; Zurich Switzerland
6. Integrierte Psychiatrie Winterthur Zürcher Unterland; Winterthur Switzerland
7. University Hospital of Psychiatry Zurich, Department of Psychiatry, Psychotherapy and Psychosomatics; University of Zurich; Zurich Switzerland