A new study published in the scientific journal Addiction estimates that in Australia between 2007 and 2016, 81% to 85% of all cannabis was consumed by the 16% of all Australian cannabis users who used daily. Weekly users and daily users together accounted for an estimated 98% of all cannabis consumed in Australia between 2007 and 2016.

This argues against the common assumption that the pattern of consumption observed with alcohol in high-income countries (in which a minority of heavy drinkers account for most of the drinking) does not apply to cannabis, which has a lower dependence risk than alcohol and many intermittent users.

Other interesting findings from this study:

Prevalence of past cannabis use in Australia increased from 8.9% in 2007 to 10.5% in 2016.

Among all past year cannabis users in Australia, 1 in 6 was a daily user.

Lead author Dr. Gary Chan, of the University of Queensland, comments: "Our study shows that the population distribution of cannabis consumption is likely to be much like alcohol, in that daily users account for the majority of total consumption. This suggests that jurisdictions with legalized cannabis should discourage heavy cannabis use by taxing cannabis products, strengthening social norms that discourage heavy consumption, restricting marketing practices that target heavy users, and screening and intervening with the heaviest cannabis users in primary care medical settings."

The study applied Monte Carlo simulation methods to four large nationally representative surveys of substance use in Australia to estimate the proportion of total cannabis consumed by daily cannabis users. One thousand simulations were generated.

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For editors:

Peer reviewed: Yes

Type of study: Simulation

Subject of study: People

Funding: Government/research council

This paper is free to download for one month after publication from the Wiley Online Library: https:/ / onlinelibrary. wiley. com/ doi/ 10. 1111/ add. 14909 (after the embargo has lifted) or by contacting Jean O'Reilly, Editorial Manager, Addiction, jean@addictionjournal.org, tel +44 (0)20 7848 0452.

To speak with co-author Dr. Gary Chan: contact him at the University of Queensland by email (c.chan4@uq.edu.au) or telephone (+61 733655488).

Full citation for article: Chan GCK and Hall W (2020) Estimation of the proportion of population cannabis consumption in Australia that is accounted for by daily users using Monte Carlo Simulation. Addiction 115: doi: 10.1111/add.14909

Funder: Department of Health, Australia

Addiction is a monthly international scientific journal publishing peer-reviewed research reports on alcohol, substances, tobacco, and gambling as well as editorials and other debate pieces. Owned by the Society for the Study of Addiction, it has been in continuous publication since 1884. Addiction is the number one journal in the 2018 ISI Journal Citation Reports ranking in the substance abuse category (science edition).