The Experimental Beverage Marketplace: Feasibility and preliminary validation of a tool to experimentally study sugar-sweetened beverage taxes and beverage purchasing.

Sugar sweetened-beverage (SSB) consumption contributes to poor diet quality and diet-related chronic diseases. One effective public health strategy to reduce SSB consumption is to tax SSB. Laboratory approaches can complement existing methods to improve understanding of how taxes on SSB influence purchasing. In this study we sought to develop and validate an experimental marketplace that presents participants with beverages typically available at grocery stores. Participants who drink SSB (n = 73) hypothetically shopped for beverages for their household with a 40% SSB tax and with no tax (order counterbalanced). Relative to the no tax condition, SSB purchasing was lower in the tax condition. We also found that self-reported beverage expenditures were correlated with experimental marketplace beverage expenditures. Most participants noticed the tax and agreed that the experimental marketplace was easy to use. Using an experimental marketplace is a promising way to explore SSB tax design to improve public policy. We present ideas for future studies that can include real and hypothetical outcomes.