How do labels using lower strength verbal descriptors, %ABV, or their combination impact wine consumption? A bar laboratory adaptive randomised controlled trial

Background and aim: A previous research study concluded that wine and beer labelled as lower in strength increase consumption compared with the same drinks labelled as regular strength. The label included both a verbal and numerical descriptor of strength. The present study aimed to estimate the effect of each of these label components. Design: Adaptive, parallel group randomised controlled trial, comprising an internal pilot sample (N1=90) and a confirmatory sample (N2=57). Setting: University bar laboratory in London UK. Participants: One-hundred and forty-seven weekly wine drinkers were sampled from a nationally representative English panel. Intervention: Participants were randomised to one of three groups to taste test wine in a bar-laboratory, varying only in the label displayed: (i) verbal descriptor only (Super Low); (ii) numerical descriptor only (4%ABV); and (iii) verbal descriptor and numerical descriptor combined (Super Low 4%ABV) [each group n = 49]. Measurements: The primary outcome was total volume (ml) of wine consumed. Findings: Participants randomised to the numerical descriptor label group (4%ABV: M = 155.12ml, B = 20.30, 95% CI = 3.92, 36.69, p-value = 0.016) and combined verbal and numerical descriptor label group (Super Low 4%ABV: M = 154.59ml, B = 20.68, 95%CI = 4.32, 37.04, p-value = 0.014) drank significantly greater amounts than those randomised to the verbal descriptor label group (Super Low: M = 125.65ml). Conclusions: This bar laboratory study estimated that a greater quantity of ‘lower’ strength wine was consumed when the label included a numerical strength descriptor compared with a verbal only strength descriptor.

This is the peer reviewed version of the following article:Vasiljevic, M., Frings, D., Pilling, M., & Marteau, T. How do labels using lower strength verbal descriptors, %ABV, or their combination impact wine consumption? A bar laboratory adaptive randomised controlled trial. Appetite , which has been published in final form at https://onlinelibrary.wiley.com/journal/13600443. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.