Australian treatment outcome study: protocol for the 18-20-year follow-up of a prospective longitudinal cohort examining the natural history of heroin dependence and associated mortality, psychiatric and physical health, and health service use.

Ethical approval has been granted for the study (Sydney Local Health District Royal Prince Alfred Zone, Human Research Ethics Committee X18-0512 & HREC/18/RPAH/733). The results of the study will be disseminated through published manuscripts, bulletins and technical reports, as well as conference, seminars, webinar and workshop presentations.