1. Institute of Mental Health, Department of Psychiatry, Faculty of Medicine University of British Columbia Vancouver BC Canada
2. Faculty of Medicine University of British Columbia Vancouver BC Canada
3. Division of Substance Use Disorders, Psychiatric Services of Thurgovia Münsterlingen Switzerland
4. Division of Substance Use Disorders University of Basel Psychiatric Clinics Basel Switzerland
5. Kian Methadone Maintenance Treatment Clinic, Private Practice Sari Mazandaran Iran
6. Rooz‐e‐No, Methadone Maintenance Treatment Clinic (Private Practice) Shiraz Fars Iran
7. Complex Pain and Addiction Consult Service Vancouver General Hospital Vancouver BC Canada
8. Addiction Institute of Mount Sinai, Department of Psychiatry Icahn School of Medicine at Mount Sinai NY USA
9. Psychosomatic Research Center Isfahan University of Medical Sciences Isfahan Iran
10. Sales, Marketing, Export and Medical Department, Darou Pakhsh Pharmaceutical Manufacturing Company Tehran Iran
11. Department of Health Management and Economics, School of Medicine AJA University of Medical Sciences Tehran Iran
12. Psychiatric Research Center, Roozbeh Hospital, Department of Psychiatry, Faculty of Medicine Tehran University of Medical Sciences Iran
13. Institute of Mental Health, Centre for Health Evaluation and Outcome Sciences, Department of Psychiatry, Faculty of Medicine University of British Columbia Vancouver BC Canada