Background: High levels of alcohol consumption are an enduring health risk among college students. Integrating multiple, complementary behavior change theories may offer a promising approach to promote reductions in alcohol consumption.
Purpose: The current study tested if integrating self-affirmation and implementation intentions would be more effective than a self-affirmation only, implementation intentions only, or control condition at reducing alcohol consumption in college students over a 2-week period.
Method: Two hundred and ninety-three college students who reported drinking in the past month were randomly assigned to a condition in a 2 (self-affirmation: values vs. control writing task) × 2 (implementation intentions: formed vs. not formed) between-subjects factorial design. Participants first completed a self-affirmation or control writing task, then read an article describing the risks of drinking. Next, all participants reported their common drinking behaviors and contexts, and then selected two harm-reduction strategies forming (or not forming) implementation intentions to use the strategies. Alcohol consumption was measured 1 and 2 weeks after the experiment.
Results: Participants in the integrated self-affirmation and implementation intention condition were most likely to abstain from drinking 1 week later. Affirmed participants continued to be more likely to abstain from drinking 2 weeks later.
Conclusions: The findings support the efficacy of integrating self-affirmation and implementation intentions to reduce college student drinking (ClinicalTrials.gov number NCT02926794).