The effect of the minimum price for unit of alcohol in Scotland on alcohol-related ambulance callouts: a controlled interrupted time series analysis.

Background and aim On the 1st of May 2018, to reduce alcohol-related harm, Scotland introduced a minimum unit price (MUP) of 0.50GBP for alcohol. It has been shown that the policy has reduced per capita alcohol consumption. The aim of this study is to assess the association between the implementation of MUP and changes in the overall volume of alcohol-related ambulance callouts. We then assessed effects on time of the day when alcohol callouts are more numerous and in specific subpopulations (e.g., different socioeconomic groups) to assess potential impacts on health inequality. Methods A controlled interrupted time series design (ITS) was used to examine variations in the daily volume of alcohol-related callouts (overall and night-time only). The control series was the number of ambulance callouts to under 13 years old. We performed uncontrolled ITS on both the intervention and control group as well as a controlled ITS built on the difference between the two series. Results No significant decrease in the volume of callouts was found in both uncontrolled series (step change: 0.062, 95%CI: -0.012,0.0135 p=0.091; slope change: -0.001, 95%CI: -0.001, 0.000 p=0.139) and controlled (step change: -0.01, 95%CI: -0.317,0.298 p=0.951; slope change: -0.003, 95%CI: -0.008, 0.002 p=0.257). Similarly, no significant changes were found for the night-time series or for any population subgroups. Conclusions There was no apparent association between the introduction of MUP and the volume of alcohol-related ambulance callouts. One possible reason for this finding may be the relatively low level of MUP, and its consequent limited effect on alcohol sales.