Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, 1120 Ave Pine, Montreal, QC, H3G 1A1, Canada.
Desautels Faculty of Management, McGill University, 1001 Ave Sherbrooke West, Montreal, QC, H3G 1G5, Canada.
Can J Public Health. 2021 Aug;112(4):638-646. doi: 10.17269/s41997-021-00479-7. Epub 2021 Mar 16.
Global consumption of caffeinated energy drinks (CED) has been increasing dramatically despite increasing evidence of their adverse health effects. Temporary price discounting is a rarely investigated but potentially powerful food marketing tactic influencing purchasing of CED. Using grocery transaction records generated by food stores in Montreal, we investigated the association between price discounting and purchasing of CED across socio-economic status operationalized by education and income levels in store neighbourhood.
The outcome, log-transformed weekly store-level sales of CED, was modelled as a function of store-level percent price discounting, store- and neighbourhood-level confounders, and an interaction term between discounting and each of tertile education and income in store neighbourhood. The model was separately fit to transactions from supermarkets, pharmacies, supercentres, and convenience stores.
There were 18,743, 12,437, 3965, and 49,533 weeks of CED sales from supermarkets, pharmacies, supercentres, and convenience stores, respectively. Percent price discounting was positively associated with log sales of CED for all store types, and the interaction between education and discounting was prominent in supercentres: -0.039 [95% confidence interval (CI): -0.051, -0.028] and -0.039 [95% CI: -0.057, -0.021], for middle- and high-education neighbourhoods relative to low-education neighbourhoods, respectively. Relative to low-income areas, the associations of discounting and log CED sales in supercentres for neighbourhoods with middle- and high-income tertile were 0.022 [95% CI: 0.010, 0.033] and 0.015 (95% CI: -0.001, 0.031), respectively.
Price discounting is an important driver of CED consumption and has a varying impact across community education and income.
尽管有越来越多的证据表明含咖啡因的能量饮料（CED）对健康有不良影响，但全球 CED 的消费仍在急剧增长。临时价格折扣是一种很少被调查但具有潜在影响力的食品营销策略，影响 CED 的购买。本研究使用蒙特利尔食品店的杂货店交易记录，调查了以商店所在社区的教育和收入水平为指标的社会经济地位与 CED 购买之间的关系。
以商店层面的 CED 每周销售对数转换为因变量，将其建模为商店层面的价格折扣百分比、商店和社区层面的混杂因素以及折扣与商店社区教育水平三分位数和收入水平的交互项的函数。该模型分别适用于来自超市、药店、超级中心和便利店的交易。
超市、药店、超级中心和便利店的 CED 销售分别有 18743、12437、3965 和 49533 周。对于所有商店类型，价格折扣百分比与 CED 的销售对数呈正相关，而教育与折扣之间的相互作用在超级中心更为显著：相对于低教育社区，中教育和高教育社区的折扣与 CED 销售之间的差异分别为 -0.039[95%置信区间（CI）：-0.051，-0.028]和 -0.039[95% CI：-0.057，-0.021]。与低收入地区相比，中等收入和高收入社区的超级中心折扣与 CED 销售的相关性分别为 0.022[95% CI：0.010，0.033]和 0.015（95% CI：-0.001，0.031）。
价格折扣是 CED 消费的一个重要驱动因素，对社区教育和收入的影响各不相同。
