The Impact on Selection of Non-Alcoholic vs Alcoholic Drink Availability: An Online Experiment
Research article
Abstract
Background
Increasing the availability of healthier food increases its selection and consumption. However, there is an absence of evidence related to alcohol. This study aimed to estimate the impact of increasing the absolute and relative availability of non-alcoholic compared to alcoholic beverages on selection. The study also assessed whether effects were modified by cognitive resource.
Methods
UK adult weekly alcohol consumers (n = 808) were recruited to an online experiment with a hypothetical beverage selection task. Participants were randomly assigned to one of eight conditions, in a 4 (availability) × 2 (cognitive resource) factorial design. The four availability conditions were: i. Reference 1 (two non-alcoholic, two alcoholic beverages); ii. Reference 2 (four non-alcoholic, four alcoholic beverages); iii. Increased non-alcoholic drinks (six non-alcoholic, two alcoholic beverages); iv. Increased alcoholic drinks (two non-alcoholic, six alcoholic beverages). The two cognitive resource conditions were: a. Low (high time pressure); b. High (low time pressure). Logistic regression was used to assess selection of a non-alcoholic beverage.
Results
49% of participants selected a non-alcoholic beverage in the Increased non-alcoholic drinks condition, compared to 36% in Reference 1, 39% in Reference 2, and 26% in the Increased alcoholic drinks condition. Non-alcoholic beverage selection was similar between Reference 1 and 2 when the total number of beverage increased (absolute availability) but the proportion of non-alcoholic compared to alcoholic beverages (relative availability) was unchanged (OR = 1.15, 95% CI 0.77, 1.73). In contrast, the odds of selecting a non-alcoholic beverage were 71% higher when both absolute and relative availability of non-alcoholic compared to alcoholic beverages was increased from Reference 1 to the Increased non-alcoholic drinks condition (OR: 1.71, 95% CI 1.15, 2.54), and 48% higher when increased from Reference 2 to the Increased non-alcoholic drinks condition (OR: 1.48, 95% CI 0.99, 2.19). There was no evidence of an effect of cognitive resource.
Conclusions
Greater availability of non-alcoholic beverages, compared to alcoholic beverages, increased their online selection, an effect that may be larger when changing their relative availability, i.e., increasing the proportion of non-alcoholic beverages. Naturalistic studies are needed to determine the impact of availability interventions on reducing alcohol purchasing and consumption.