1. BC Centre for Excellence in HIV/AIDS; BC Centre on Substance Use; 611 Powell Street Vancouver BC Canada V6A 1H2
2. School of Medicine, University College Dublin; Health Science Centre, Belfield, UCD Dublin Ireland D4
3. University College Dublin; School of Medicine; Dublin Ireland
4. National University of Ireland Galway; College of Medicine, Nursing, & Health Sciences, School of Health Sciences Galway Ireland
5. Faculty of Education and Health Sciences, University of Limerick; Graduate Entry Medical School; Limerick Ireland
6. Graduate Entry Medical School, University of Limerick; Department of Paediatrics; Limerick Ireland
7. Graduate Entry Medical School, University of Limerick; General Practice; Limerick Ireland
8. Health Service Executive; Addiction Services; Bridge House, Cherry Orchard Hospital Ballyfermot Dublin Ireland 10
9. Graduate Entry Medical School, University of Limerick; Statistical Consulting Unit/ Applied Biostatistics Consulting Centre /CSTAR; Limerick Ireland
10. Faculty of Education and Health Sciences, University of Limerick; Centre for Interventions in Infection, Inflammation & Immunity (4i); Limerick Ireland