Evaluating the impact of minimum unit pricing (MUP) on alcohol sales after 3 years of implementation in Scotland: A controlled interrupted time-series study.

BACKGROUND AND AIMS: On 1 May 2018, Scotland introduced minimum unit pricing (MUP), a strength-based floor price below which alcohol cannot be sold, throughout all alcoholic beverages. The legislation necessitates an evaluation of its impact across a range of outcomes that will inform whether MUP will continue beyond its sixth year. We measured the impact of MUP on per-adult alcohol sales (as a proxy for consumption) after 3 years of implementation.

DESIGN, SETTING AND PARTICIPANTS: Controlled interrupted time-series regression was used to assess the impact of MUP on alcohol sales in Scotland after 3 years of implementation, with England and Wales (EW) being the control group. In adjusted analyses, we included household disposable income, on-trade alcohol sales (in off-trade analyses) and substitution between drink categories (in drink category analyses) as covariates.

MEASUREMENTS: Weekly data were assessed on the volume of pure alcohol sold in Scotland and EW between January 2013 and May 2021, expressed as litres of pure alcohol per adult. The impact of MUP on total (on- and off-trade combined), off-trade and on-trade alcohol sales was assessed separately.

RESULTS: The introduction of MUP in Scotland was associated with a 3.0% (95% confidence interval = 1.8-4.2%) net reduction in total alcohol sales per adult after adjustment for the best available geographical control, disposable income and substitution. This reflects a 1.1% fall in Scotland in contrast to a 2.4% increase in EW. The reduction in total alcohol sales in Scotland was driven by reduced sales of beer, spirits, cider and perry. The reduction in total sales was due to reductions in sales of alcohol through the off-trade. There was no evidence of any change in on-trade alcohol sales.

CONCLUSION: Minimum unit pricing has been effective in reducing population-level alcohol sales in Scotland in the 3 years since implementation.