Inclusion criteria

Eligible PWID were aged ≥18 years, reported injecting illicit drugs in the last six months and were living or working in Songkhla province. They were also agreeable and able to provide informed consent, and had a valid referral coupon. Potential participants were screened by asking them to show injection marks. If no injection marks were observed, they would be asked to describe and/or demonstrate how they prepare and inject drugs. PWID who were intoxicated at the time of the survey were excluded from the survey.