An N‐of‐1 study of daily alcohol consumption following minimum unit pricing implementation in Scotland

• Published in: Addiction (Abingdon, England) England), 2021-07, Vol.116 (7), p.1725-1733
• Main Authors: Kwasnicka, Dominika, Boroujerdi, Massoud, O'Gorman, Aileen, Anderson, Martin, Craig, Peter, Bowman, Louise, McCann, Mark
• Format: Article
• Language: English
• Subjects: Adult; Adults; Alcohol; Alcohol Drinking - epidemiology; alcohol policy; Alcohol use; Alcoholic Beverages; Alcoholism; Behavior modification; behaviour change; Change agents; Changes; Commerce; Consumption; Consumption patterns; Costs and Cost Analysis; Drinking behavior; Drug abuse; Drug dependence; ecological momentary assessment; Health risks; Humans; Individual differences; Licensed premises; minimum unit price; Motivation; N‐of‐1; Observational studies; Policy making; Polls & surveys; Psychosocial factors; Public health; Research Report; Research Reports; Response rates; Rural areas; Rural communities; Scotland - epidemiology; Social factors; Social interactions; Social networks; Social organization; Substance abuse; Substance use
• ISSN: 0965-2140; 1360-0443
• DOI: 10.1111/add.15382

Background and aims Within the context of Scotland's policy change to implement a minimum unit price (MUP) per unit of alcohol sold in licensed premises, this study used an N‐of‐1 design to assess between‐person differences in the psychological and social factors associated with daily alcohol consumption. Design and setting A mixed‐methods approach combined N‐of‐1 observational studies, comprising daily surveys followed by qualitative social network interviews (not reported here). Peer researchers with lived experience of substance use were involved in the study design and fieldwork was conducted in towns and rural areas in the East of Scotland. Participants/cases Twenty‐five adults with current or recent history of alcohol dependence recruited for three 12‐week waves: 11 in wave 1 (pre‐MUP), 11 in wave 2 (pre‐ and post‐MUP) and three in wave 3 (post MUP). Measurements Gender, age, alcohol and other drug use history. Daily surveys for 12 weeks captured information about factors in the last 24 hours, e.g. amount and type of alcohol consumed, stress, social contact. Findings Each participant was in the daily survey for a mean of 64 days [standard deviation (SD) = 42; median = 59], with a response rate of 48%; 15 participants provided sufficient data for analysis. Factors related to daily alcohol consumption differed between individuals. Models suggested that some individuals with high initial consumption reduced drinking after MUP, but explanatory factors differed, e.g. changing motivation was important for some, while alcohol availability was important for others. Conclusions Adapting N‐of‐1 methods for an observational study uncovered differences in alcohol consumption change before and after minimum unit pricing implementation in Scotland, evidence of individual differences in the factors relating to alcohol consumption patterns and some evidence that post‐MUP consumption changes may be related to changing psychosocial factors.