Background and Aims: The shape of glassware may exacerbate or counteract biases in perceived volume, which may lead people to misjudge the pouring of alcoholic drinks. The aim of these studies was to investigate the effect of glass shape on the pouring accuracy of liquid volume. Methods: In Study 1, using an online computerised task, participants (n = 211) were asked to pour liquid in glasses in a within-subjects design with factors of glass shape (straight, curved) and requested percentage fullness (10, 20, 25, 30, 40, 50, 60, 70, 75, 80, 90%). Curve estimations were carried out to determine if errors followed a linear or non-linear relationship. In Study 2, participants (n = 96) were asked to pour water to the midpoint of pint glasses in a within-subjects design with one factor of glass shape (straight, curved, tulip, inverted). Differences between poured amounts were analysed using one-way repeated measures ANOVA.Results: In Study 1, participants under-poured in curved glasses compared to straight glasses at all requested amounts. In Study 2, participants under-poured in curved (p < 0.001, dz = 1.51) and tulip (p < 0.001, dz = 0.59) glasses compared to straight glasses. Findings were inconclusive as to whether or not a difference was present between pourings in inverted and straight glasses. Participants displayed a tendency to under-pour in all glasses relative to requested amounts in both studies.Conclusions: The shape of glassware appears to influence the pouring accuracy of liquid. Pouring in tulip and curved glasses was more inaccurate compared to straight glasses, possibly due to the height of liquid within the glass and volume changing in a non-linear relationship. Glassware that promotes more accurate pouring may lead to slower alcohol consumption.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.