Effectiveness of alcohol warning labels for at-risk groups and the general public: A policy-informing randomized experiment in Chile.

OBJECTIVE: The World Health Organization recommends using health-risk warnings on alcoholic beverages. This study examines the impact of separate or combined warning labels for at-risk groups and the general population on alcohol purchase decisions. METHODS: In 2022, 7758 adults who consumed alcohol or were pregnant/lactating women (54.0 % female, mean age = 40.6 years) were presented with an online store's beverage section and randomly assigned to one of six warning labels in a between-subjects experimental design: no-warning, pregnant/lactating, drinking-driving, general cancer risk, combined warnings, and assorted warnings across bottles. The main outcome, the intention to purchase an alcoholic vs. non-alcoholic beverage, was examined with adjusted risk differences using logistic regressions. RESULTS: Participants exposed to the general cancer risk warning decreased their alcoholic choices by 10.4 percentage points (pp.) (95 % CI [-0.139, -0.069], p < 0.001, OR = 0.561), while those in the pregnancy/lactation warning condition did it by 3.8 pp. (95 % CI [-0.071, -0.005], p = 0.025, OR = 0.806). The driving-drinking warning had no significant effect. Participants exposed to the combined warnings label, or the assorted warnings reduced alcohol purchase decisions by 6.1 pp. (95 % CI [-0.095, -0.028], p < 0.001, OR = 0.708) and 4.3 pp. (95 % CI [-0.076, -0.010], p = 0.011, OR = 0.782), respectively. Cancer warning outperformed other labels and was effective for subgroups such as pregnant/lactating women, young adults, and low-income individuals. CONCLUSIONS: General cancer risk warnings are more effective at reducing alcohol purchase decisions compared to warning labels for specific groups or labels using multiple warnings. In addition to warning labels, other policies should be considered for addressing well-known alcohol-related risks (e.g., drinking and driving).