PROJECT ABSTRACT Nearly 1 in 3 American adults exceed the recommended limit for alcohol consumption, increasing their risk of health problems including hypertensive heart disease, injuries, and several types of cancer. Most adults are not aware of the harms of alcohol consumption. Evidence-based warnings on alcohol containers that are displayed prominently on the front of the package, include pictorial elements such as icons, and rotate their content over time could inform consumers and discourage unhealthy alcohol consumption. The overarching objective of this proposal is to evaluate the impact of evidence-based alcohol warnings on alcohol consumption. In Aim 1, we will use existing research and expert review to optimize warning statements describing the health harms of alcohol consumption. We will then test an array of evidence-based warnings in a randomized experiment with a nationally representative sample of 910 adult regular alcohol consumers. The main product of Aim 1 will be the selection of 4 evidence-based warnings that participants endorse as effective for use in Aim 2. In Aim 2, we will evaluate the impact of these evidence-based alcohol warnings on alcohol consumption in a longitudinal RCT. We will recruit 786 adult regular alcohol consumers. Participants will be randomly assigned to a warnings arm or a control arm. In a 4-week study, participants in the warnings arm will receive the 4 unique evidence-based warnings affixed to their alcohol containers, allocated in random order. In the control arm, no new labels will be applied. We will assess whether the evidence-based alcohol warnings reduce number of drinks consumed (measured using daily diaries) and examine whether this effect varies by baseline alcohol use, gender, age, and education. We will also evaluate how warnings influence potential psychological mediators (measured in weekly surveys). The final product of Aim 2 will be an estimate of the impact of evidence-based alcohol warnings on alcohol consumption. In Aim 3, we will validate a model of how alcohol warnings influence alcohol consumption. We will conduct in-depth interviews with participants in the warnings arm of Aim 2’s RCT to elicit insights about the mechanisms through which the trial warnings influenced their behavior. Then, we will apply mediation analyses to the longitudinal daily diary and survey data collected in Aim 2’s RCT to identify mediators of the impact of the trial warnings on alcohol consumption. The final product of Aim 3 will be a model of how evidence-based alcohol warnings influence alcohol consumption. This research is responsive to NOT-AA-21-028 by conducting causal analyses of an alcohol-reduction policy and advancing methods by implementing an innovative RCT with naturalistic exposure to warnings. Our findings will create an evidence base to inform development of effective alcohol warnings as well as other communication campaigns. Ultimately, new evidence-based alcohol warnings could reduce unhealthy alcohol consumption and address rising rates of alcohol-attributable disease and death in the US and globally.

PROJECT NARRATIVE Alcohol consumption is a leading cause of death and disability in the United States. Requiring evidence-based health warnings on alcohol containers could inform consumers and reduce unhealthy alcohol consumption, but there is little data on how such warnings influence alcohol consumption. The proposed research will optimize evidence-based warnings about the health harms of alcohol consumption and evaluate their effectiveness at reducing alcohol consumption among regular alcohol consumers in the US.