Australian drug trends 2021: key findings from the National Illicit Drug Reporting System (IDRS) interviews.

The IDRS sample is a sentinel group aged 18 years or older who injected illicit drugs at least once monthly in the preceding six months and resided in the capital cities of Australia. Participants were recruited via advertisements in needle syringe programs and other harm reduction services, as well as via peer referral. The results are not representative of all people who use illicit drugs, nor of use in the general population. Data were collected in 2021 from June-July. Interviews in 2020 and 2021 were delivered face-to-face as well as via telephone, due to COVID-19 restrictions being imposed in various jurisdictions throughout the data collection periods. This methodological change should be factored into all comparisons of data from the 2020 and 2021 sample relative to previous years.