Using a 3D virtual supermarket to measure food purchase behavior: a validation study

Becoming Healthier without Paying More? Experimental Evidence from the Impact of Multiple Traffic Lights on Chinese College Students

The prevalence of overweight and obesity among Chinese residents has become a pressing public health concern. The UK Multiple Traffic Light labeling system, known for its user-friendly design, has demonstrated success in promoting healthier food choices. This paper presents novel findings from a randomized controlled experiment assessing the impact of traffic light labeling on Chinese consumers' food choices. Results indicate that the label significantly reduces the intake of calories, fat, carbohydrates, and sodium without increasing the economic costs of food choices. This study contributes empirical evidence to the effectiveness of traffic light labeling in China, with implications for the country's approach to front-of-pack nutrition labeling.

Assessing the usability of an immersive virtual reality grocery store in healthy controls

BACKGROUND

Immersive virtual reality (IVR) as a research platform to study human behaviors is an emerging field and may be useful for studying self-care management, especially in the gap between formal healthcare recommendations and day-to-day living. Self-care activities, such as grocery shopping, can be challenging for people with chronic illness. We developed an IVR environment that simulates a real-life grocery store and conducted a usability study to demonstrate the safety and acceptability of IVR as an experimental environment.

METHODS

This study was a three-arm randomized control trial involving 24 participants, conducted as a usability study to evaluate aspects of the experimental condition including the effectiveness of a training exposure, the occurrence of undesirable effects associated with IVR, and participants' experiences of realism, immersion, and spatial presence. The experiment, using a head mounted device and handheld controllers, included a 10-minute training exposure, followed by one of three unique 30-minute experimental conditions which exposed participants to different combinations of tasks and stimuli, and a post-experience interview. We measured controller errors, undesirable symptoms associated with IVR, and the perception of realism, immersion, and spatial presence.

RESULTS

Participants used controllers effectively to interact within the IVR environment. Hand controller use errors were fewer during the experimental conditions compared to the training exposure. Minimal undesirable IVR symptoms were reported. Presence was rated in the middle range with no significant differences based on experimental condition. Overall, user experience feedback was positive.

CONCLUSIONS

We demonstrated that participants could engage in our IVR environment without excessive error or experiencing undesirable effects and confirmed that the virtual experience attained a level of presence necessary to effectively engage in the study. These findings give us confidence that this IVR intervention designed to explore instrumental activities of daily living is safe, effective and provides a credible, controlled simulated community-like setting.

The effects of health-related food taxes on the environmental impact of consumer food purchases: secondary analysis of data from a randomised controlled trial in a virtual supermarket

OBJECTIVE

To measure the effects of health-related food taxes on the environmental impact of consumer food purchases in a virtual supermarket.

DESIGN

This is a secondary analysis of data from a randomised controlled trial in which participants were randomly assigned to a control condition with regular food prices (n 152), an experimental condition with a sugar-sweetened beverage (SSB) tax (n 131) or an experimental condition with a nutrient profiling tax based on Nutri-Score (n 112). Participants were instructed to undertake their typical weekly grocery shopping for their households. Primary outcome measures were three environmental impact indicators: greenhouse gas (GHG) emissions, land use and blue water use per household per week. Data were analysed using linear regression analyses.

SETTING

Three-dimensional virtual supermarket.

PARTICIPANTS

Dutch adults (≥ 18 years) who were responsible for grocery shopping in their household (n 395).

RESULTS

GHG emissions (-7·6 kg CO2-eq; 95 % CI -12·7, -2·5) and land use (-3·9 m2/year; 95 % CI -7·7, -0·2) were lower for the food purchases of participants in the nutrient profiling tax condition than for those in the control condition. Blue water use was not affected by the nutrient profiling tax. Moreover, the SSB tax had no significant effect on any of the environmental impact indicators.

CONCLUSIONS

A nutrient profiling tax based on Nutri-Score reduced the environmental impact of consumer food purchases. An SSB tax did not affect the environmental impact in this study.

Changing the default order of food items in an online grocery store may nudge healthier food choices

Restructuring food environments, such as online grocery stores, has the potential to improve consumer health by encouraging healthier food choices. The aim of this study was to investigate whether repositioning foods within an experimental online grocery store can be used to nudge healthier choices. Specifically, we investigated whether repositioning product categories displayed on the website main page, and repositioning individual products within those categories, will influence selection. Adults residing in Australia (n = 175) were randomised to either intervention (high-fibre foods on top) or comparator condition (high-fibre foods on the bottom). Participants completed a shopping task using the experimental online grocery store, with a budget of up to AU$100 to for one person's weekly groceries. The results of this study show that the total fibre content per 100 kcal per cart (p < .001) and total fibre content per cart (p = .036) was higher in the intervention compared to comparator condition. Moreover, no statistical difference between conditions was found for the total number of fibre-source foods (p = .67), the total energy per cart (p = .17), and the total grocery price per cart (p = .70) indicating no evidence of implications for affordability. Approximately half of the participants (48%) reported that they would like to have the option to sort foods based on a specific nutrient criterion when shopping online. This study specifically showed that presenting higher-fibre products and product categories higher up on the online grocery store can increase the fibre content of customers' purchases. These findings have important implications for consumers, digital platform operators, researchers in health and food domains, and for policy makers.

Portion size affects food selection in an immersive virtual reality buffet and is related to measured intake in laboratory meals varying in portion size

A crucial step for validating the utility of an immersive virtual reality (iVR) buffet to study eating behavior is to determine whether variations in food characteristics such as portion size (PS) are relevant predictors of food selection in an iVR buffet. We tested whether manipulating PS in an iVR buffet affects the weight of food selected, and whether this response to PS is similar to participants' measured intake when PS varies at laboratory meals. In a randomized crossover design, 91 adults (18-71 y; 64 females; BMI = 25.3 ± 5.7) used their iVR remote to select lunch and dinner portions from an iVR buffet before consuming a standardized lab meal at two visits separated by one week. The PS in the iVR buffet and lab meals varied between a standard PS and a large PS. This design enabled comparisons of PS effects between iVR and lab settings, despite the scale difference in food weight between the environments. Portion size significantly affected food selection and food intake (p < 0.001). Subjects selected an additional 350 g in iVR and consumed an additional 154 g of food in the lab meals when offered the large portion compared to the small portion. The effect of PS showed a similar percentage increase in iVR (36.5%) and lab meals (39.2%). There was no significant difference in the effect of PS between iVR and lab meals after accounting for scale differences in food weight between the environments. The response to PS was not influenced by subject characteristics such as body mass index, sex, or age. These results demonstrate the utility of iVR for replicating real-world eating behaviors and enhancing our understanding of the intricate dynamics of food-related behaviors in a variety of contexts.

The impact of calorie labelling and proportional pricing on out of home food orders: a randomised controlled trial study using a virtual food and drink delivery app

BACKGROUND

Mandatory calorie labelling in the out-of-home food sector was introduced in England in 2022, and menu pricing strategies that ensure cost is equivalent to portion size (proportional pricing) have been proposed as a policy to reduce obesity. Food delivery app-based platforms now contribute significantly to diet, and evidence suggests that those at a socioeconomic disadvantage may have greater exposure to unhealthy options on these platforms. However, public health policies to improve nutritional quality of food ordered from food delivery apps has received limited examination.

OBJECTIVE

This experimental study assessed the impact of calorie labelling and proportional pricing on item and meal size selection, calories ordered, and money spent when selecting food and drinks from three outlet types on a virtual delivery app.

METHODS

UK adult participants (N = 1126, 49% female), stratified by gender and education level completed an online study where they ordered items from three branded food and beverage outlets (coffee shop, sandwich outlet, fast food outlet) using a virtual delivery app. Participants were presented food and beverage options with vs. without calorie labels and with value (larger portions are proportionally cheaper) vs. proportional pricing.

RESULTS

Calorie labelling did not influence portion size selection for any outlets, but significantly reduced calories ordered from the coffee shop (-18.95kcals, 95% CI -33.07 to -4.84) and fast food outlet (-54.19kcals, 95% CI -86.04 to -22.33). Proportional pricing reduced the likelihood of choosing a larger beverage from the coffee shop (OR = 0.58, 95% CI 0.45 to 0.75), but was associated with increased calories ordered from the fast food outlet (51.25kcals, 95% CI 19.59 to 82.90). No consistent interactions were observed with participant characteristics, suggesting that effects of calorie labelling and pricing on outcomes were similar across sociodemographic groups.

CONCLUSIONS

Calorie labelling on food delivery platforms may effectively reduce calories ordered. Proportional pricing may be useful in prompting consumers to select smaller portion sizes, although further research in real-world settings will now be valuable.

The gamification of nutrition labels to encourage healthier food selection in online grocery shopping: A randomized controlled trial

Food purchase choices, one of the main determinants of food consumption, is highly influenced by food environments. Given the surge in online grocery shopping because of the COVID-19 pandemic, interventions in digital environments present more than ever an opportunity to improve the nutritional quality of food purchase choices. One such opportunity can be found in gamification. Participants (n = 1228) shopped for 12 items from a shopping list on a simulated online grocery platform. We randomized them into four groups in a 2 × 2 factorial design: presence vs. absence of gamification, and high vs. low budget. Participants in the gamification groups saw foods with 1 (least nutritious) to 5 (most nutritious) crown icons and a scoreboard with a tally of the number of crowns the participant collected. We estimated ordinary least squares and Poisson regression models to test the impact of the gamification and budget on the nutritional quality of the shopping basket. In the absence of gamification and low budget, participants collected 30.78 (95% CI [30.27; 31.29]) crowns. In the gamification and low budget condition, participants increased the nutritional quality of their shopping basket by collecting more crowns (B = 4.15, 95% CI [3.55; 4.75], p < 0.001). The budget amount ($50 vs. $30) did not alter the final shopping basket (B = 0.45, 95% CI [-0.02; 1.18], p = 0.057), nor moderated the gamification effect. Gamification increased the nutritional quality of the final shopping baskets and nine of 12 shopping list items in this hypothetical experiment. Gamifying nutrition labels may be an effective strategy to improve the nutritional quality of food choices in online grocery stores, but further research is needed.

Immersive and desktop virtual reality in virtual fashion stores: a comparison between shopping experiences

With the high growth and prosperity of e-commerce, the retail industry needs to explore new technologies that improve digital shopping experiences. In the current technological scenario, Virtual Reality (VR) emerges as a tool and an opportunity for enhancing shopping activities, especially for the fashion industry. This study explores whether using Immersive Virtual Reality (IVR) technologies enhances the shopping experience in the fashion industry compared to Desktop Virtual Reality (DVR). A within-subject experiment was carried out involving a sample of 60 participants who completed a simulated shopping experience. In the first mode (DVR), a desktop computer setup was used to test the shopping experience using a mouse and keyboard for navigation. The second mode (IVR) exploited a Head-Mounted Display (HMD), and controllers, that allowed navigation while seated on a workstation to avoid sickness. Participants had to find a bag in the virtual shop and explore its features until they were ready to purchase it. Post-hoc measures of time duration of the shopping experience, hedonic and utilitarian values, user experience, and cognitive load were compared. Results showed that participants experienced higher hedonism and utilitarianism in the IVR shop compared to DVR. The cognitive load was comparable in both modes, while user experience was higher in IVR. In addition, the time duration of the shopping experience was higher in IVR, where users stayed immersed and enjoyed it for longer. This study has implications for fashion industry research, as the use of IVR can potentially lead to novel shopping patterns by enhancing the shopping experience.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10055-023-00806-y.

Traffic-light front-of-pack environmental labelling across food categories triggers more environmentally friendly food choices: a randomised controlled trial in virtual reality supermarket

BACKGROUND

Food systems highly contribute to anthropogenic greenhouse gas emissions and shifting towards more environmentally friendly diets is urgently needed. Enabling consumers to compare the environmental impact of food products at point-of-purchase with front-of-pack labelling could be a promising strategy to trigger more environmentally friendly food choices. This strategy remained to be tested.

METHODS

The effect of a new traffic-light front-of-pack environmental label on food choices was tested in a 2-arm randomised controlled trial in a virtual reality supermarket. Participants (n = 132) chose food products to compose two main meals for an everyday meal scenario and for an environmentally friendly meal scenario with or without the label. The environmental label (ranging from A: green/lowest impact, to E: red/highest impact) was based on the Environmental Footprint (EF) single score calculation across food categories. The effect of the label on the environmental impact of food choices in each scenario was tested using linear mixed models.

RESULTS

In the everyday meal scenario, the environmental impact of meals was lower in the label condition than in the no label condition (-0.17 ± 0.07 mPt/kg, p = 0.012). This reduction was observed at no nutritional, financial nor hedonic cost. The effectiveness of the label can be attributed to a change in the food categories chosen: less meat-based and more vegetarian meals were chosen with the label. In the environmentally friendly meal scenario, we demonstrated that the label provided new information to the participants as they were able to further reduce the environmental impact of their food choices with the label (-0.19 ± 0.07 mPt/kg, p = 0.005).

CONCLUSIONS

Implementing a front-of-pack environmental label on food products in real supermarkets could increase awareness of the environmental impact of food and contribute to drive more environmentally friendly food choices.

TRIAL REGISTRATION

The study protocol was pre-registered prior to data collection at Clinicaltrials.gov (NCT04909372).

Consumer behaviour and experiences in a naturalistic online grocery store: implications for nutrition research

Naturalistic online grocery stores could provide a novel setting for evaluating nutrition interventions. In 2021–2022, we recruited US adults (n 144, 59% low-income) to complete two weekly study visits: one in a naturalistic (‘mock’) online grocery store developed for research and one in a real online grocery store. Participants selected groceries and responded to survey questions. Analyses examined survey responses and expenditures on fifteen food categories (e.g., bread, sugar-sweetened beverages). Nearly all enrolled participants completed both visits (98% retention). Moreover, nearly participants all reported that their selections in the naturalistic store were similar to their usual purchases (95%) and that the naturalistic store felt like a real store (92%). Participants’ spending on food categories in the naturalistic store were moderately-to-strongly correlated with their spending in the real store (range of correlation coefficients: 0⋅36–0⋅67, all P-values < 0⋅001). Naturalistic online grocery stores may offer a promising platform for conducting nutrition research.

Exploring the effects of added sugar labels on food purchasing behaviour in Australian parents: An online randomised controlled trial

Background

Evidence of the effects of front-of-pack added sugar labelling remains limited, especially for foods other than sugary drinks. More information is needed about which labels are likely to be most effective in reducing intended purchases of products with higher added sugar content in realistic contexts to inform policymakers’ decisions.

Objective

To determine the impact of added sugar labels on intended purchases of high sugar breakfast cereals, yoghurt, and non-alcoholic beverages.

Methods

Australian parents who were regular purchasers of relevant product categories completed an online parallel randomised controlled trial from 31 August 2020 to 13 February 2021. Participants selected their intended purchase from 10 products in each of packaged beverages, breakfast cereal, and yoghurt categories after randomisation to one of seven added sugar labelling conditions in current use or under consideration by the Australian Government. Logistic regressions assessed differences between intervention and control conditions in the odds of intended purchases of a high sugar product.

Results

2825 eligible participants were randomised with 2582 valid surveys analysed (Control n = 367; ‘Nutrition Information Panel (NIP) with Added Sugar’ n = 364; ‘Teaspoons of Sugar’ n = 369; ‘Warning’ n = 371; ‘Health Star Rating (HSR) using Total Sugar’ n = 368; ‘HSR with Added Sugar’ n = 371; ‘Sugar in the Ingredients List’ n = 372). No consistent effects were found on intended purchases of high sugar products overall or within product categories for any of the tested labels compared to controls (overall, ‘NIP with Added Sugar’: OR 1.00 [95%CI 0.83,1.20]; ‘Teaspoons of Sugar’: 0.94[0.80,1.11]; ‘Warning’: 1.10[0.93,1.30]; ‘HSR with Total Sugar’: 1.01[0.85,1.21]; ‘HSR with Added Sugar’: 1.09[0.92,1.30]; ‘Sugar in the Ingredients List’: 1.01[0.85,1.21]).

Conclusions

Findings reinforce the importance of ensuring nutrition labelling policies are introduced as part of a suite of interventions to influence both consumer and manufacturer behaviour.

Trial registration

Australian New Zealand Clinical Trials Registry, ACTRN12620000858998. Registered 28 August 2020, https://anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12620000858998.

Less meat in the shopping basket. The effect on meat purchases of higher prices, an information nudge and the combination: a randomised controlled trial

Background

Reduced meat consumption benefits human and planetary health. Modelling studies have demonstrated the significant health and environmental gains that could be achieved through fiscal measures targeting meat. Adding other interventions may enhance the effect of a fiscal measure. The current study aimed to examine the effect of higher meat prices, an information nudge and a combination of both measures on meat purchases in a three-dimensional virtual supermarket.

Methods

A parallel designed randomised controlled trial with four conditions was performed. Participants (≥ 18 years) were randomly assigned to the control condition or one of the experimental conditions: a 30% price increase for meat (‘Price condition’), an information nudge about the environmental impact of meat production and consumers’ role in that regard (‘Information nudge condition’) or a combination of both (‘Combination condition’). Participants were asked to shop for their household for one week. The primary outcome was the difference in the total amount of meat purchased in grams per household per week.

Results

Between 22 June 2020 and 28 August 2020, participants were recruited and randomly assigned to the control and experimental conditions. The final sample included 533 participants. In the ‘Combination condition’, − 386 g (95% CI: − 579, − 193) meat was purchased compared with the ‘Control condition’. Compared to the ‘Control condition’ less meat was purchased in the ‘Price condition’ (− 144 g (95%CI: − 331, 43)), although not statistically significant, whereas a similar amount of meat was purchased in the ‘Information nudge condition’ (1 g (95%CI: − 188, 189)).

Conclusion

Achieving the most pronounced effects on reduced meat purchases will require a policy mixture of pricing and informational nudging. Less meat is purchased in a virtual supermarket after raising the meat price by 30% combined with an information nudge. The results could be used to design evidence-based policy measures to reduce meat purchases.

Trial registration

The trial was registered in the Netherlands Trial Register identifier NL8628. Registered on 18/05/2020. ICTRP Search Portal (who.int) NTR (trialregister.nl).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-13535-9.

Nutrition-related claims lead parents to choose less healthy drinks for young children: a randomized trial in a virtual convenience store

BACKGROUND

Consumption of sugar-sweetened beverages, including fruit drinks (i.e., fruit-flavored drinks containing added sugar), contributes to childhood obesity.

OBJECTIVES

We aimed to examine whether nutrition-related claims on fruit drinks influence purchasing among parents and lead to misperceptions of healthfulness.

METHODS

We conducted an experiment in a virtual convenience store with 2219 parents of children ages 1-5 y. Parents were randomly assigned to view fruit drinks displaying 1 of 3 claims ("No artificial sweeteners," "100% Vitamin C," and "100% All Natural") or no claim (i.e., control group). Parents selected among each of 2 drinks for their young child: 1) a fruit drink or 100% juice (primary outcome), and 2) a fruit drink or water.

RESULTS

When choosing between a fruit drink and 100% juice, 45% of parents who viewed the fruit drink with the "No artificial sweeteners" claim, 51% who viewed the "100% Vitamin C" claim, and 54% who viewed the "100% All Natural" claim selected the fruit drink, compared with 32% in the no-claim control group (all P < 0.001). "No artificial sweeteners" (Cohen's d = 0.13, P < 0.05) and "100% All Natural" (d = 0.15, P < 0.05) claims increased the likelihood of parents choosing the fruit drink instead of water but "100% Vitamin C" did not (P = 0.06). All claims made parents more likely to incorrectly believe that the fruit drinks contained no added sugar and were 100% juice than the control (d ranged from 0.26 to 0.84, all P < 0.001), as assessed in a posttest survey. The impact of claims on selection of the fruit drink (compared with 100% juice) did not vary by any of the moderators examined (e.g., race/ethnicity, income; all moderation P > 0.05).

CONCLUSIONS

Nutrition-related claims led parents to choose less healthy beverages for their children and misled them about the healthfulness of fruit drinks. Labeling regulations could mitigate misleading marketing of fruit drinks.This trial was registered at clinicaltrials.gov as NCT04381481.

The effects of a sugar-sweetened beverage tax and a nutrient profiling tax based on Nutri-Score on consumer food purchases in a virtual supermarket: a randomised controlled trial

OBJECTIVE

To investigate the effects of a sugar-sweetened beverage (SSB) tax and a nutrient profiling tax on consumer food purchases in a virtual supermarket.

DESIGN

A randomised controlled trial was conducted with a control condition with regular food prices (n 152), an SSB tax condition (n 130) and a nutrient profiling tax condition based on Nutri-Score (n 112). Participants completed a weekly grocery shop for their household. Primary outcome measures were SSB purchases (ordinal variable) and the overall healthiness of the total shopping basket (proportion of total unit food items classified as healthy). The secondary outcome measure was the energy (kcal) content of the total shopping basket. Data were analysed using regression analyses.

SETTING

Three-dimensional virtual supermarket.

PARTICIPANTS

Dutch adults aged ≥18 years are being responsible for grocery shopping in their household (n 394).

RESULTS

The SSB tax (OR = 1·62, (95 % CI 1·03, 2·54)) and the nutrient profiling tax (OR = 1·88, (95 %CI 1·17, 3·02)) increased the likelihood of being in a lower-level category of SSB purchases. The overall healthiness of the total shopping basket was higher (+2·7 percent point, (95 % CI 0·1, 5·3)), and the energy content was lower (-3301 kcal, (95 % CI -6425, -177)) for participants in the nutrient profiling tax condition than for those in the control condition. The SSB tax did not affect the overall healthiness and energy content of the total shopping basket (P > 0·05).

CONCLUSIONS

A nutrient profiling tax targeting a wide range of foods and beverages with a low nutritional quality seems to have larger beneficial effects on consumer food purchases than taxation of SSB alone.

Examining the neural correlates of goal priming with the NeuroShop, a novel virtual reality fMRI paradigm

OBJECTIVE

Health goal priming has been shown to stimulate healthy food choices by activating an individual's weight-control goal. The present study combined fMRI with a novel virtual reality food choice task to elucidate the underlying neural mechanisms of health goal priming. Previous research has suggested that the ventromedial prefrontal cortex (vmPFC) and dorsolateral prefrontal cortex (dlPFC) play a role in the incorporation of health considerations into the food choice process. Responses may be more representative for those found in real life when assessed in an environment similar to the actual choice environment. Therefore, the first aim of the study was to explore if a novel virtual reality food choice task is sufficiently sensitive to detect basic valuation processes in food choice. The second aim was to examine whether increased activation in the dlPFC drives the effects of health goal priming.

METHODS

Fifty-six female participants performed an fMRI food choice task embedded in a virtual supermarket environment. They chose between perceived healthy and unhealthy products in a health prime, hedonic prime, and non-food control condition, while activation in brain areas involved in self-control and valuation (vmPFC, dlPFC) was assessed.

RESULTS

There were no differences in relative preference for perceived healthy products over unhealthy products between the conditions. There were also no main effects of prime condition on brain activation in the vmPFC and dPFC during food choice. Across conditions, activation in the vmPFC correlated with the tastiness of the chosen product during food choice.

CONCLUSIONS

Although the study does not provide support for health goal priming triggering neural self-control mechanisms, results did show that virtual reality has potential for a more realistic fMRI food choice paradigm.

Are nudging and pricing strategies on food purchasing behaviors equally effective for all? Secondary analyses from the Supreme Nudge virtual supermarket study

Nudging and pricing strategies are effective in promoting healthier purchases. However, whether the effects are equal across individuals with different personal characteristics is unknown. This exploratory study aimed to examine differential effects of nudging and pricing strategies on food purchases across individuals' levels of impulsivity, price sensitivity, decision-making styles, and food choice motives. Data from a virtual supermarket experiment where participants were exposed to five study conditions (control, nudging, pricing, salient pricing, and salient pricing with nudging) was used. Participants completed questionnaires assessing their impulsivity, price sensitivity, decision-making styles, and food choice motives. The outcome was the percentage of healthy food purchases. Effect modification was analyzed by adding interaction terms to the statistical models and post-hoc probing was conducted for statistically significant interaction terms. We used data from 400 Dutch adult participants (61.3% female, median age 30.0 years (IQR 24.0)). The effects of the nudging and pricing conditions on healthy food purchases were not modified by impulsivity, price sensitivity, decision-making styles, and the food choice motives 'health' and 'price'. Only the interactions of the food choice motive 'natural content of foods' x pricing (B = -1.02, 90%CI = -2.04; -0.01), the food choice motive 'weight control' x nudging (B = -2.15, 90%CI = -3.34; -0.95), and 'weight control' x pricing (B = -1.87, 90%CI = -3.11; -0.62) were statistically significant. Post-hoc probing indicated that nudging and/or pricing strategies were more effective in individuals who gave lower priority to these food choice motives. The effects of nudging and pricing strategies on increasing healthy food purchasing behaviors, at least in a virtual environment, do not seem to be influenced by personal characteristics and may therefore be implemented as general health promoting strategies.

Impact of taxes on purchases of close substitute foods: analysis of cross-price elasticities using data from a randomized experiment

OBJECTIVE

To examine the effects of health-related food taxes on substitution and complementary purchases within food groups, including from unhealthier to healthier alternatives and between brands.

METHODS

We used data from a virtual supermarket experiment with data from 4,259 shopping events linked to varying price sets. Substitution or complementary effects within six frequently purchased food categories were analyzed. Products' own- and cross-price elasticities were analyzed using Almost Ideal Demand System models.

RESULTS

Overall, 37.5% of cross-price elasticities were significant (p < 0.05) and included values greater than 0.10. Supplementary and complementary effects were particularly found in the dairy, meats and snacks categories. For example, a 1% increase in the price of high saturated fat dairy was associated with a 0.18% (SE 0.06%) increase in purchases of low saturated fat dairy. For name- and home-brand products, significant substitution effects were found in 50% (n = 3) of cases, but only in one case this was above the 0.10 threshold.

CONCLUSIONS/POLICY IMPLICATIONS

Given the relatively low own-price elasticities and the limited substitution and complementary effects, relatively high taxes are needed to substantively increase healthy food purchases at the population level.

TRIAL REGISTRATION

This study included secondary analyses; the original trial was registered in the Australian New Zealand Clinical Trials Registry ACTRN12616000122459 .

A Standardized Guide to Developing an Online Grocery Store for Testing Nutrition-Related Policies and Interventions in an Online Setting

Simulated online grocery store platforms are innovative tools for studying nutrition-related policies and point-of-selection/point-of-purchase interventions in online retail settings, yet there is no clear guidance on how to develop these platforms for experimental research. Thus, we created a standardized guide for the development of an online grocery store, including a detailed description of (1) methods for acquiring and cleaning online grocery store data, and (2) how to design a two-dimensional online grocery store experimental platform. We provide guidance on how to address product categorization, product order/sorting and product details, including how to identify outliers and conflicting nutritional information and methods for standardizing prices. We also provide details regarding our process of “tagging” food items that can be leveraged by future studies examining policies and point-of-selection/point-of-purchase interventions targeting red and processed meat and fruits and vegetables. We experienced several challenges, including obtaining accurate and up-to-date product information and images, and accounting for the presence of store-brand products. Regardless, the methodology described herein will enable researchers to examine the effects of a wide array of nutrition-related policies and interventions on food purchasing behaviors in online retail settings, and can be used as a template for reporting procedures in future research.

Shifting toward a healthier dietary pattern through nudging and pricing strategies: A secondary analysis of a randomized virtual supermarket experiment

BACKGROUND

Nudging and salient pricing are promising strategies to promote healthy food purchases, but it is possible their effects differ across food groups.

OBJECTIVE

To investigate in which food groups nudging and/or pricing strategies most effectively changed product purchases and resulted in within-food groups substitutions or spillover effects.

METHODS

In total, 318 participants successfully completed a web-based virtual supermarket experiment in the Netherlands. We conducted a secondary analysis of a mixed randomized experiment consisting of 5 conditions (within subject) and 3 arms (between subject) to investigate the single and combined effects of nudging (e.g., making healthy products salient), taxes (25% price increase), and/or subsidies (25% price decrease) across food groups (fruit and vegetables, grains, dairy, protein products, fats, beverages, snacks, and other foods). Generalized linear mixed models were used to estimate the incidence rate ratios and 95% CIs for changes in the number of products purchased.

RESULTS

Compared with the control condition, the combination of subsidies on healthy products and taxes on unhealthy products in the nudging and price salience condition was overall the most effective, as the number of healthy purchases from fruit and vegetables increased by 9% [incidence rate ratio (IRR) = 1.09; 95% CI: 1.02, 1.18], grains by 16% (IRR = 1.16; 95% CI: 1.05, 1.28), and dairy by 58% (IRR = 1.58; 95% CI: 1.31, 1.89), whereas the protein and beverage purchases did not significantly change. Regarding unhealthy purchases, grains decreased by 39% (IRR = 0.72; 95% CI: 0.63, 0.82) and dairy by 30% (IRR = 0.77; 95% CI: 0.68, 0.87), whereas beverage and snack purchases did not significantly change. The groups of grains and dairy showed within-food group substitution patterns toward healthier products. Beneficial spillover effects to minimally targeted food groups were seen for unhealthy proteins (IRR = 0.81; 95% CI: 0.73, 0.91).

CONCLUSIONS

Nudging and salient pricing strategies have a differential effect on purchases of a variety of food groups. The largest effects were found for dairy and grains, which may therefore be the most promising food groups to target in order to achieve healthier purchases. The randomized trial on which the current secondary analyses were based is registered in the Dutch trial registry (NTR7293; www.trialregister.nl).

Recruitment of Participants for a 3D Virtual Supermarket: Cross-sectional Observational Study

Background

Virtual supermarkets offer a practical and affordable setting to test the efficacy of different pricing and nudging strategies before they are implemented in the real world. Despite the advantages of using virtual supermarkets for this purpose, conducting studies in online settings is challenging with regard to recruitment and retention of sufficient and suitable participants.

Objective

To describe cost, time, and retention with regard to participants recruited using various strategies and potential sociodemographic differences between participants recruited via different strategies.

Methods

This cross-sectional study used data from a randomized controlled trial in which 455 Dutch adults with low and high educational levels were invited to shop 5 times in a 3D virtual supermarket. Participants were recruited via social media and flyers. A log that tracked the costs of and time spent on the different recruitment strategies was kept by the study team. Outcome measures included the cost of recruitment strategies, the time investment by researchers, and recruitment and attrition rates of participants in the study.

Results

The median age of study completers was 31.0 (IQR 25.0) and 157 out of 346 study completers (45.4%) were highly educated. Out of the 455 included participants, 235 (51.6%) were recruited via social media campaigns, 131 (28.8%) via home-delivered flyers, 38 (8.4%) via flyers directly distributed by the study team, and 46 (10.1%) via word-of-mouth. Of all paid recruitment strategies, social media campaigns were the cheapest and least time-consuming, whereas the distribution of flyers by the study team was the most expensive and time-consuming recruitment strategy. Age, sex, overweight status, employment situation, and number of adults within the household varied by recruitment strategy.

Conclusions

Using different recruitment strategies resulted in the efficient recruitment of a representative study sample and retention of participants was relatively high. While “word-of-mouth” was the most cost- and time-effective recruitment strategy, using only one type of recruitment strategy could result in a demographically skewed study population.

Under pressure: Nudging increases healthy food choice in a virtual reality supermarket, irrespective of system 1 reasoning

Previous research has shown that nudging can effectively support people's healthy food choices. Yet, to date knowledge about the psychological premises of nudging is limited, highlighting the need for closer scrutiny to determine how and when nudging is most effective. In the current study, we assessed whether the presumed effect of nudging on healthy food choice is enhanced under time pressure, a condition probing alleged system 1 reasoning. Food choice was studied in a realistic virtual reality supermarket where healthier alternatives were nudged by making them more salient. We additionally explored possible differences in decision-making experiences related to nudging or time pressure. The study took place at a science festival where visitors could decide to participate in a study. Participants (n = 99) had to purchase four products, each from a different product category that was provided on a shopping list. In the nudging condition, one healthier option within each product category was nudged by making it more salient. While a main effect of nudging was found, showing in increased healthy food choices, this effect was not further qualified by time pressure, suggesting that the effectiveness of nudging is not enhanced under system 1 conditions. Relatedly, people who were and who were not aware of the nudges showed similar effects of nudging on healthy food choice. Furthermore, no differences in decision-making experiences showed, suggesting that people have similar experiences regarding impulsive and reflective decision-making irrespective of whether they are being nudged or put under time pressure. All in all, our findings are in line with recent viewpoints on the premises of nudges, suggesting that alleged system 1 conditions are not a prerequisite for nudging to be effective.

Effects of Labelling and Increasing the Proportion of Lower-Energy Density Products on Online Food Shopping: A Randomised Control Trial in High- and Low-Socioeconomic Position Participants

Reducing the energy density (ED) of product selections made during online supermarket food shopping has potential to decrease energy intake. Yet it is unclear which types of intervention are likely to be most effective and equitable. We recruited 899 UK adults of lower and higher socioeconomic position (SEP) who completed a shopping task in an online experimental supermarket. Participants were randomised in a 2 × 2 between-subjects design to test the effects of two interventions on the ED of shopping basket selections: labelling lower-ED products as healthier choices and increasing the relative availability of lower-ED products within a range (referred to as proportion). Labelling of lower-ED products resulted in a small but significant decrease (−4.2 kcal/100 g, 95% CIs −7.8 to −0.6) in the ED of the shopping basket. Increasing the proportion of lower-ED products significantly decreased the ED of the shopping basket (−17 kcal/100 g, 95% CIs −21 to −14). There was no evidence that the effect of either intervention was moderated by SEP. Thus, both types of intervention decreased the ED of foods selected in an online experimental supermarket. There was no evidence that the effectiveness of either intervention differed in people of lower vs. higher SEP.

Low-Income Parents' Use of Front-of-Package Nutrition Labels in a Virtual Supermarket

OBJECTIVE

To examine the impact front-of-package nutrition labels (FOPLs) have on decision-making abilities among low-income parents in a virtual supermarket.

DESIGN

A 4-by-2 experimental design with 3 FOPLs (summary, nutrient-specific, hybrid) and a no-FOPL comparison. Within the FOPL condition, participants either shopped with a time limit (10 minutes) or with no time limit.

SETTING

A web-based, 3-dimensional virtual supermarket.

PARTICIPANTS

Parents (n = 1,452) from low-income households with at least 1 child aged 4-12 years.

MAIN OUTCOMES MEASURED

Index derived from the United Kingdom's Nutrient Profiling Model that summarized the overall nutrient profile of the participant's shopping basket.

ANALYSIS

Analysis of covariance with post hoc estimations (pairwise) of condition means adjusted for multiple comparisons.

RESULTS

All FOPLs led to healthier nutrient profiles than the no-FOPL condition (P < .001). Simple FOPLs (ie, summary, hybrid) led to healthier nutrient profiles than nutrient-specific FOPLs (P = .02 and P < .001, respectively). Among parents exposed to simple FOPLs, those under time pressure made less healthy choices than those who were not under time pressure (P = .05 and P = .03, respectively). Time pressure did not affect parents exposed to nutrient-specific FOPLs (P = .69).

CONCLUSIONS AND IMPLICATIONS

Front-of-package nutrition labels can aid parents in selecting healthier products. Simple FOPLs provide greater utility for selecting healthier products than FOPLs that present an array of nutrient information. Time pressure can influence how parents interact with different types of label information.

The effects of nudging and pricing on healthy food purchasing behavior in a virtual supermarket setting: a randomized experiment

BACKGROUND

Evidence on what strategies - or combination of strategies - are most effective and equitable in promoting healthier diets is needed. This study examined the efficacy of nudging and pricing strategies on increasing healthy food purchases and the potential differential effect by socio-economic position (SEP) among Dutch adults in a virtual supermarket.

METHODS

A randomized study design was conducted within a virtual supermarket (SN VirtuMart). Participants were exposed to five within-subject study conditions (control, nudging, pricing, price salience and price salience with nudging) and randomized to one of three between-subject study arms (a 25% price increase on unhealthy products, a 25% discount on healthy products, or a 25% price increase and discount). In total, 455 participants of low and high SEP (using either education or income as proxy) were randomized to conduct their weekly shopping in a virtual supermarket for five consecutive weeks. The primary outcome included the percentage of healthy purchases. Data were analyzed using linear mixed models.

RESULTS

In total, 346 (76%) adults completed all five shops within the SN VirtuMart. Median age was 32.5, 49.2% had high education and 32.8% had high income. Out of the 12 conditions, four conditions were statistically significantly different from the control condition. Nudging and non-salient pricing strategies alone did not statistically significantly increase healthy food purchases, whereas a combination of salient price increases and discounts led to an increase in the percentage of healthy food purchases (B 4.5, 95%CI 2.6; 6.4). Combining salient pricing and nudging strategies led to increases in the percentage of healthy products in all three pricing arms, with largest effects found in the combined price increase and discount arm (B = 4.0, 95%CI = 2.0; 6.0). Effects were not modified by SEP.

CONCLUSIONS

Combining health-related price increases and discounts and combining these salient pricing strategies with nudges in a supermarket setting seems to stimulate healthy food purchases for both low and high SEP populations. However, further research in real-world settings is needed.

TRIAL REGISTRATION

This randomized trial ( NTR7293 ) was registered in the Dutch trial registry ( www.trialregister.nl ).

Feasibility of a virtual reality-based interactive feedback program for modifying dysfunctional communication: a preliminary study

Background

Functional communication is vital in many areas of daily life, and modifying dysfunctional communication has been emphasized in various social areas, including family and school. The present preliminary study addressed the feasibility of a virtual reality (VR)-based interactive feedback program for the modification of dysfunctional communication.

Methods

Thirty-seven healthy young males completed psychological assessments associated with functional communication and participated in the VR-based program, consisting of the three tasks of ‘exploring the communication style,’ ‘practicing functional communication,’ and ‘expressing empathy.’ Behavioral parameters were recorded based on the participants’ choices among available options and the visual analog scale scores that resulted in responses to questions in the tasks.

Results

Participants completed the program without dropping-out and reported 10.76 (SD, 9.66) in the Simulator Sickness Questionnaire and 106.97 (SD, 16.66) in the Presence Questionnaire. In exploring the communication style, there was no difference between the dysfunction level-with family and dysfunction level-with a friend, but only the dysfunction level-with family showed significant correlations with the level of communication with parents. In practicing functional communication, the communication scores with the placating, blaming, and computing styles significantly increased according to the repetition of trials. In expressing empathy, the empathetic feeling score was negatively correlated with the perspective-taking score, whereas the emotional intensity score was positively correlated with the level of differentiation of the self.

Conclusion

These results suggest that the program may have a tolerable level of cybersickness, an adequate level of presence, an improvement in the behavioral parameters that may reflect the important aspects of communication, and a proper reflection of psychological states or interpersonal characteristics. The use of this program can be an important starting point for the development of a more convenient method for delivering VR programs designed to modify dysfunctional communication, which can further increase computerized dissemination.

Socioeconomic position and the impact of increasing availability of lower energy meals vs. menu energy labelling on food choice: two randomized controlled trials in a virtual fast-food restaurant

BACKGROUND

Food consumed outside of the home is often high in energy and population level interventions that reduce energy intake of people from both lower and higher socioeconomic position (SEP) are needed. There is a lack of evidence on the effectiveness and SEP equity of structural-based (e.g. increasing availability of lower energy options) and information provision (e.g. menu energy labelling) interventions on food choice.

METHODS

Across two online experiments, participants of lower and higher SEP made meal choices in a novel virtual fast-food restaurant. To be eligible to take part, participants were required to be UK residents, aged 18 or above, fluent in English, have access to a computer with an internet connection and have no dietary restrictions. Participants were randomized to one of four conditions in a 2 × 2 between-subjects design: menu energy labelling present vs. absent and increased availability of lower energy options (75% of menu options lower energy) vs. baseline availability (25% of menu options lower energy). Participants also completed measures of executive function and food choice motives.

RESULTS

The analysis of pooled data from both studies (n = 1743) showed that increasing the availability of lower energy options resulted in participants ordering meals with significantly less energy on average (- 71 kcal, p <  0.001, partial η2 = 0.024) and this effect was observed irrespective of participant SEP. Menu labelling had no significant effect on energy ordered (- 18 kcal, p = 0.116, partial η2 = 0.001) in participants from both higher and lower SEP. Furthermore, we found no evidence that executive function or food choice motives moderated the effect of increasing lower energy menu options or energy labelling on total energy ordered.

CONCLUSIONS

In a virtual fast-food environment, energy labelling was ineffective in reducing total energy ordered for both higher and lower SEP participants. Increasing the availability of lower energy options had an equitable effect, reducing total energy ordered in participants from higher and lower SEP.

TRIAL REGISTRATION

Study protocols and analysis plans were pre-registered on the Open Science Framework (https://osf.io/ajcr6/).

A Virtual Home for the Virtual Clinical Trial

Virtual clinical trials (VCTs) can satisfy the need for rigorous clinical trials by using distributed technological solutions that eliminate the need for a physical trial site. This report explores potential benefits of using virtual reality (VR) to provide a "virtual site" for VCTs, a shared immersive hub in which VCT participants could experience elements of the trial and interact with the trial team. VR is a communication technology that has been emerging alongside the development of VCTs, although they have never been merged in a substantial way. Many of the gaps within the VCT paradigm are areas in which VR excels. VR environments are standardized and precisely uniform, the technology allows introduction of an almost endless set of stimuli to participants' visual and auditory systems, and VR systems are adept at capturing precise movement and behavioral data. Although VR has not yet found its way into VCTs, much of the groundwork for such integration has been laid through research and technological development achieved in the past few years. Future implementation of VR within VCTs could move us from site-less trials to those with a virtual site serving as a hub for trial information provision, interaction with trial representatives, administration of evaluations and assessments, and more.

Antismoking Advertisements and Price Promotions and Their Association With the Urge to Smoke and Purchases in a Virtual Convenience Store: Randomized Experiment

Background

Point of sale (POS) advertising is associated with smoking initiation, current smoking, and relapse among former smokers. Price promotion bans and antismoking advertisements (ads) are 2 possible interventions for combating POS advertising.

Objective

The purpose of this analysis was to determine the influence of antismoking ads and promotions on urges to smoke and tobacco purchases.

Methods

This analysis examined exposure to graphic (graphic images depicting physical consequences of tobacco use) and supportive (pictures of and supportive messages from former smokers) antismoking ads and promotions in a virtual convenience store as predictors of urge to smoke and buying tobacco products among 1200 current cigarette smokers and 800 recent quitters recruited via a Web-based panel (analytical n=1970). We constructed linear regression models for urge to smoke and logistic regression models for the odds of purchasing tobacco products, stratified by smoking status.

Results

The only significant finding was a significant negative relationship between exposure to supportive antismoking ads and urge to smoke among current smokers (beta coefficient=−5.04, 95% CI −9.85 to −0.22; P=.04). There was no significant relationship between graphic antismoking ads and urge to smoke among current smokers (coefficient=−3.77, 95% CI −8.56 to 1.02; P=.12). Neither relationship was significant for recent quitters (graphic: coefficient=−3.42, 95% CI −8.65 to 1.81; P=.15 or supportive: coefficient=−3.82, 95% CI −8.99 to 1.36; P=.20). There were no significant differences in urge to smoke by exposure to promotions for current smokers (coefficient=−1.06, 95% CI −4.53 to 2.41; P=.55) or recent quitters (coefficient=1.76, 95% CI −2.07 to 5.59; P=.37). There were also no differences in tobacco purchases by exposure to graphic (current smokers: coefficient=0.93, 95% CI 0.67 to 1.29; P=.66 and recent quitters: coefficient=0.73, 95% CI 0.44 to 1.19; P=.20) or supportive (current smokers: coefficient=1.05, 95% CI 0.75 to 1.46; P=.78 and recent quitters: coefficient=0.73, 95% CI 0.45 to 1.18; P=.20) antismoking ads or price promotions (current smokers: coefficient=1.09, 95% CI 0.86 to 1.38; P=.49 and recent quitters: coefficient=0.90, 95% CI 0.62 to 1.31; P=.60).

Conclusions

The results of this analysis support future research on the ability of supportive antismoking ads to reduce urges to smoke among current cigarette smokers. Research on urges to smoke has important tobacco control implications, given the relationship between urge to smoke and smoking cigarettes, time to next smoke, and amount smoked.

Virtual Reality in Marketing: A Framework, Review, and Research Agenda

Marketing scholars and practitioners are showing increasing interest in Extended Reality (XR) technologies (XRs), such as virtual reality (VR), augmented reality (AR), and mixed reality (MR), as very promising technological tools for producing satisfactory consumer experiences that mirror those experienced in physical stores. However, most of the studies published to date lack a certain measure of methodological rigor in their characterization of XR technologies and in the assessment techniques used to characterize the consumer experience, which limits the generalization of the results. We argue that it is necessary to define a rigorous methodological framework for the use of XRs in marketing. This article reviews the literature on XRs in marketing, and provides a conceptual framework to organize this disparate body of work.

Good practice in food-related neuroimaging

The use of neuroimaging tools, especially functional magnetic resonance imaging, in nutritional research has increased substantially over the past 2 decades. Neuroimaging is a research tool with great potential impact on the field of nutrition, but to achieve that potential, appropriate use of techniques and interpretation of neuroimaging results is necessary. In this article, we present guidelines for good methodological practice in functional magnetic resonance imaging studies and flag specific limitations in the hope of helping researchers to make the most of neuroimaging tools and avoid potential pitfalls. We highlight specific considerations for food-related studies, such as how to adjust statistically for common confounders, like, for example, hunger state, menstrual phase, and BMI, as well as how to optimally match different types of food stimuli. Finally, we summarize current research needs and future directions, such as the use of prospective designs and more realistic paradigms for studying eating behavior.

A Virtual Reality Food Court to Study Meal Choices in Youth: Design and Assessment of Usability

Background

Regular consumption of take-out and fast foods with sugary drinks is associated with poor quality diets and higher prevalence of obesity. Among the settings where such food is consumed is the food court typically found in shopping malls prominent in many countries.

Objective

The objective of this research was to develop a virtual reality food court that could be used to test food environmental interventions, such as taxation, and ultimately to facilitate the selection of healthier food choices.

Methods

Fourteen food courts in Sydney, Australia were selected to include those in the city center and suburbs of high and low socioeconomic status. Researchers visited the courts to collect information on number and type of food outlets, all menu items for sale, cost of foods and beverages and sales promotions. This information was used to assemble 14 food outlets typically found in food courts, and representative menus were compiled. The UNITY gaming platform was used to design a virtual reality food court that could be used with HTC VIVE goggles. Participants navigated the virtual reality food court using the head-mounted display, keyboard, and mouse and selected a lunch meal, including food and beverage. A validated questionnaire on presence within the virtual reality food court and system usability was completed at the end of the session. The constructs for presence included a sense of control, sensory fidelity, realism, distraction, and involvement. Questions were rated on a scale from 1 (worst) through 7 (best) for each of 28 questions giving a maximum total score of 196. The systems usability scale (SUS) that gives a final score out of 100 was also assessed.

Results

One hundred and sixty-two participants with a mean age of 22.5 (SD 3.1) years completed the survey. The mean score for total presence was 144 (SE 1.4) consisting of control: 62.1 (SE 0.8), realism: 17.5 (SE 0.2), involvement: 9.6 (SE 0.2), sensory fidelity: 34.9 (SE 0.4), and distraction: 24.0 (SE 0.3). The mean SUS was 69 (SE 1.1).

Conclusions

Virtual reality shows promise as a tool to study food choice for test interventions to inform practice and policy.

Influence of Being Embodied in an Obese Virtual Body on Shopping Behavior and Products Perception in VR

Research in Virtual Reality (VR) showed that embodiment can influence participants' perceptions and behavior when embodied in a different yet plausible virtual body. In this paper, we study the changes an obese virtual body has on products perception (e.g., taste, etc.) and purchase behavior (e.g., number purchased) in an immersive virtual retail store. Participants (of a normal BMI on average) were embodied in a normal (N) or an obese (OB) virtual body and were asked to buy and evaluate food products in the immersive virtual store. Based on stereotypes that are classically associated with obese people, we expected that the group embodied in obese avatars would show a more unhealthy diet, (i.e., buy more food products and also buy more products with high energy intake, or saturated fat) and would rate unhealthy food as being tastier and healthier than participants embodied in “normal weight” avatars. Our participants also rated the perception of their virtual body: the OB group perceived their virtual body as significantly heavier and older. They also rated their sense of embodiment and presence within the immersive virtual store. These measures did not show any significant difference between groups. Finally, we asked them to rate different food products in terms of tastiness, healthiness, sustainability and price. The only difference we noticed is that participants embodied in an obese avatar (OB group) rated the coke as being significantly tastier and the apple as being significantly healthier. Nevertheless, while we hypothesized that participants embodied in a virtual body with obesity would show differences in their shopping patterns (e.g., more “unhealthy” products bought) there were no significant differences between the groups. Stereotype activation failed for our participants embodied in obese avatars, who did not exhibit a shopping behavior following the (negative) stereotypes related to obese people. conversely, while the opposite hypothesis (participants embodied in obese avatars would buy significantly more healthy products in order to “transform” their virtual bodies) could have been made, it was not the case either. We discuss these results and propose hypotheses as to why the behavior of the manipulated group differed from the one we expected. Indeed, unlike previous research, our participants were embodied in virtual avatars which differed greatly from their real bodies. Obese avatars should not only modify users' visual characteristics such as hair or skin color, etc. We hypothesize that an obese virtual body may require some other non-visual stimulus, e.g., the sensation of the extra weight or the change in body size. This main difference could then explain why we did not notice any important modification on participants' behavior and perceptions of food products. We also hypothesize that the absence of stereotype activation and thus of statistical difference between our N and OB groups might be due to higher-level cognitive processes involved while purchasing food products. Indeed our participants might have rejected their virtual bodies when performing the shopping task, while the embodiment and presence ratings did not show significant differences, and purchased products based on their real (non-obese) bodies. This could mean that stereotype activation is more complex that previously thought.

Deception and Shopping Behavior Among Current Cigarette Smokers: A Web-Based, Randomized Virtual Shopping Experiment

BACKGROUND

Virtual stores can be used to identify influences on consumer shopping behavior. Deception is one technique that may be used to attempt to increase the realism of virtual stores.

OBJECTIVE

The objective of the experiment was to test whether the purchasing behavior of participants in a virtual shopping task varied based on whether they were told that they would receive the products they selected in a virtual convenience store (a form of deception) or not.

METHODS

We recruited a US national sample of 402 adult current smokers by email from an online panel of survey participants. They completed a fully automated randomized virtual shopping experiment with a US $15 or US $20 budget in a Web-based virtual convenience store. We told a random half of participants that they would receive the products they chose in the virtual store or the cash equivalent (intervention condition), and the other random half simply to conduct a shopping task (control condition). We tested for differences in demographics, tobacco use behaviors, and in-store purchases (outcome variable, assessed by questionnaire) by experimental condition.

RESULTS

The characteristics of the participants (398/402, 99.0% with complete data) were comparable across conditions except that the intervention group contained slightly more female participants (103/197, 52.3%) than the control group (84/201, 41.8%; P=.04). We did not find any other significant differences in any other demographic variables or tobacco use, or in virtual store shopping behaviors, including purchasing any tobacco (P=.44); purchasing cigarettes (P=.16), e-cigarettes (P=.54), cigars (P=.98), or smokeless tobacco (P=.72); amount spent overall (P=.63) or on tobacco (P=.66); percentage of budget spent overall (P=.84) or on tobacco (P=.74); number of total items (P=.64) and tobacco items purchased (P=.54); or total time spent in the store (P=.07).

CONCLUSIONS

We found that telling participants that they will receive the products they select in a virtual store did not influence their purchases. This finding suggests that deception may not affect consumer behavior and, as a result, may not be necessary in virtual shopping experiments.

Visual Search for Wines with a Triangle on the Label in a Virtual Store

Two experiments were conducted in a virtual reality (VR) environment in order to investigate participants’ in-store visual search for bottles of wines displaying a prominent triangular shape on their label. The experimental task involved virtually moving along a wine aisle in a virtual supermarket while searching for the wine bottle on the shelf that had a different triangle on its label from the other bottles. The results of Experiment 1 revealed that the participants identified the bottle with a downward-pointing triangle on its label more rapidly than when looking for an upward-pointing triangle on the label instead. This finding replicates the downward-pointing triangle superiority (DPTS) effect, though the magnitude of this effect was more pronounced in the first as compared to the second half of the experiment, suggesting a modulating role of practice. The results of Experiment 2 revealed that the DPTS effect was also modulated by the location of the target on the shelf. Interestingly, however, the results of a follow-up survey demonstrate that the orientation of the triangle did not influence the participants’ evaluation of the wine bottles. Taken together, these findings reveal how in-store the attention of consumers might be influenced by the design elements in product packaging. These results therefore suggest that shopping in a virtual supermarket might offer a practical means of assessing the shelf standout of product packaging, which has important implications for food marketing.

Using a UK Virtual Supermarket to Examine Purchasing Behavior Across Different Income Groups in the United Kingdom: Development and Feasibility Study

BACKGROUND

The majority of food in the United Kingdom is purchased in supermarkets, and therefore, supermarket interventions provide an opportunity to improve diets. Randomized controlled trials are costly, time-consuming, and difficult to conduct in real stores. Alternative approaches of assessing the impact of supermarket interventions on food purchases are needed, especially with respect to assessing differential impacts on population subgroups.

OBJECTIVE

The aim of this study was to assess the feasibility of using the United Kingdom Virtual Supermarket (UKVS), a three-dimensional (3D) computer simulation of a supermarket, to measure food purchasing behavior across income groups.

METHODS

Participants (primary household shoppers in the United Kingdom with computer access) were asked to conduct two shopping tasks using the UKVS and complete questionnaires on demographics, food purchasing habits, and feedback on the UKVS software. Data on recruitment method and rate, completion of study procedure, purchases, and feedback on usability were collected to inform future trial protocols.

RESULTS

A total of 98 participants were recruited, and 46 (47%) fully completed the study procedure. Low-income participants were less likely to complete the study (P=.02). Most participants found the UKVS easy to use (38/46, 83%) and reported that UKVS purchases resembled their usual purchases (41/46, 89%).

CONCLUSIONS

The UKVS is likely to be a useful tool to examine the effects of nutrition interventions using randomized controlled designs. Feedback was positive from participants who completed the study and did not differ by income group. However, retention was low and needs to be addressed in future studies. This study provides purchasing data to establish sample size requirements for full trials using the UKVS.

Using a Virtual Store As a Research Tool to Investigate Consumer In-store Behavior

People's responses to products and/or choice environments are crucial to understanding in-store consumer behaviors. Currently, there are various approaches (e.g., surveys or laboratory settings) to study in-store behaviors, but the external validity of these is limited by their poor capability to resemble realistic choice environments. In addition, building a real store to meet experimental conditions while controlling for undesirable effects is costly and highly difficult. A virtual store developed by virtual reality techniques potentially transcends these limitations by offering the simulation of a 3D virtual store environment in a realistic, flexible, and cost-efficient way. In particular, a virtual store interactively allows consumers (participants) to experience and interact with objects in a tightly controlled yet realistic setting. This paper presents the key elements of using a desktop virtual store to study in-store consumer behavior. Descriptions of the protocol steps to: 1) build the experimental store, 2) prepare the data management program, 3) run the virtual store experiment, and 4) organize and export data from the data management program are presented. The virtual store enables participants to navigate through the store, choose a product from alternatives, and select or return products. Moreover, consumer-related shopping behaviors (e.g., shopping time, walking speed, and number and type of products examined and bought) can also be collected. The protocol is illustrated with an example of a store layout experiment showing that shelf length and shelf orientation influence shopping- and movement-related behaviors. This demonstrates that the use of a virtual store facilitates the study of consumer responses. The virtual store can be especially helpful when examining factors that are costly or difficult to change in real life (e.g., overall store layout), products that are not presently available in the market, and routinized behaviors in familiar environments.

Development and standardization of the "Let's Shop" questionnaire: an assessment of shopping habits and executive functions in people with obesity

Overweight and obesity are epidemic in Western countries and the literature suggests a relationship between overweight and executive functions (EF). Shopping is a regular, everyday activity that is strongly related to executive functioning. To date, no assessment tool has been developed to evaluate EF in adults with overweight and obesity, with a focus on the activity of shopping. To determine the factorial validity of the newly developed "Let's Shop" questionnaire. A convenience sample which included three groups of 93 men and women aged 35-60 were included in the study. Thirty three overweight participants and 30 obese participants who sought a clinical dietitian constituted the two research groups, and 30 normal weight participants recruited from a physician's waiting room constituted the control group and were matched to the two research groups by age, gender, education, and socioeconomic status. The "Let's Shop" questionnaire was administered to all participants. An exploratory principal factor extraction with oblimin rotation was conducted for the "Let's Shop" questionnaire. Twenty-one items were entered into the equation; the analysis revealed four distinct factors comprised of 17 items. The cumulative percentage of variance accounted for by the four factors was 44.74%. The four factors were as follows: "planning in action" α = 0.63; "planning ahead" α = 0.71; "impulsivity" α = 0.67; and "habits" α = 0.63. The "Let's Shop" questionnaire was reduced to 17 items. This brief questionnaire will enable rapid administration by researchers and practitioners and determine a potential association between EF in the supermarket arena and weight status.

Study protocol: combining experimental methods, econometrics and simulation modelling to determine price elasticities for studying food taxes and subsidies (The Price ExaM Study)

Background

There is a need for accurate and precise food price elasticities (PE, change in consumer demand in response to change in price) to better inform policy on health-related food taxes and subsidies.

Methods/Design

The Price Experiment and Modelling (Price ExaM) study aims to: I) derive accurate and precise food PE values; II) quantify the impact of price changes on quantity and quality of discrete food group purchases and; III) model the potential health and disease impacts of a range of food taxes and subsidies. To achieve this, we will use a novel method that includes a randomised Virtual Supermarket experiment and econometric methods. Findings will be applied in simulation models to estimate population health impact (quality-adjusted life-years [QALYs]) using a multi-state life-table model. The study will consist of four sequential steps:

We generate 5000 price sets with random price variation for all 1412 Virtual Supermarket food and beverage products. Then we add systematic price variation for foods to simulate five taxes and subsidies: a fruit and vegetable subsidy and taxes on sugar, saturated fat, salt, and sugar-sweetened beverages.

Using an experimental design, 1000 adult New Zealand shoppers complete five household grocery shops in the Virtual Supermarket where they are randomly assigned to one of the 5000 price sets each time.

Output data (i.e., multiple observations of price configurations and purchased amounts) are used as inputs to econometric models (using Bayesian methods) to estimate accurate PE values.

A disease simulation model will be run with the new PE values as inputs to estimate QALYs gained and health costs saved for the five policy interventions.

Discussion

The Price ExaM study has the potential to enhance public health and economic disciplines by introducing internationally novel scientific methods to estimate accurate and precise food PE values. These values will be used to model the potential health and disease impacts of various food pricing policy options. Findings will inform policy on health-related food taxes and subsidies.

Trial registration

Australian New Zealand Clinical Trials Registry ACTRN12616000122459 (registered 3 February 2016).