The sample consisted of 399 heroin users, of whom 63% were male. The mean age of participants was 31 years (SD 8.2, range 17, 58). The majority of participants were born in Australia (78%), a small proportion of which identified as another ethnic group. Participants were categorised as either 'Australian' (67%), Indigenous (17%) or 'other-Australian' (16%). The majority (81%) of participants had attended secondary school, but only 42 (11%) participants had tertiary education. Thirty-four (9%) participants had completed primary (elementary) school only. Sixty-one percent of participants had a history of incarceration.
