Combining implementation intentions and monetary incentives to reduce alcohol use: a failed generalization to a public bar context

ABSTRACT

Background

Implementation intentions have been demonstrated to reduce alcohol use in retrospective self-report measures. It remains unclear, however, whether they can moderate drinking in a challenging naturalistic context. We examined this by studying the effects of implementation intentions on alcohol use in a bar.

Methods

One hundred and twenty-one participants visiting a local bar were randomized over three conditions: control, motivational trigger, and motivational trigger plus implementation intentions. Those in the motivational trigger group were motivated to reduce drinking, and the combined intervention group made additional alcohol-related implementation intentions. We assessed participants’ pre- and post-intervention breath alcohol concentrations, their post-intervention drinking behavior over one hour, and measures of trait impulsivity and reward sensitivity. To predict post-intervention drinking, multiple hierarchical regression was used.

Results

Neither the motivational trigger nor the added implementation intentions reduced drinking. Across treatment groups, trait impulsivity predicted alcohol consumption.

Conclusions

The present study showed that motivational trigger and implementation intentions failed to reduce alcohol use in a naturalistic setting. Potential reasons, implications, and limitations are discussed. This first attempt demonstrates that implementation intentions aimed at moderation are not as easily implemented in a public high-risk context.

KEYWORDS:

• Alcohol
• implementation intentions
• motivation
• self-control
• bar study

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/14659891.2022.2070876

Notes

1. This is a proof-of-principle study rather than a randomized controlled trial, as we tested short-lived changes in behavior in a non-clinical sample (c.f., Boffo et al., 2019).

2. It is worth noting that the meta-analysis with a specific focus on addiction (Malaguti et al., 2020) was only published after we have completed our data collection. Therefore, the relatively small effect size of implementation intentions in reducing alcohol use was not referred to when determine the sample size here.

3. Compared to locals, they should be less likely to compensate their good times to comply with the instructions.

4. $\mathrm{\Delta }\mathrm{B}\mathrm{r}\mathrm{A}\mathrm{C}=\mathrm{B}\mathrm{r}\mathrm{A}\mathrm{C}2+0.15-\mathrm{B}\mathrm{r}\mathrm{A}\mathrm{C}1$, where 0.15 is the hourly metabolism rate of alcohol for moderate drinkers (Jones, 2010).

5. This was BrAC1 in $\mathrm{\Delta }\mathrm{B}\mathrm{r}\mathrm{A}\mathrm{C}$-based regression, and grams of ethanol already had in self-reported measure-based regression.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.