The efficacy of nudge theory strategies in influencing adult dietary behaviour: a systematic review and meta-analysis

Acceptance of healthy lifestyle nudges in the general population of Singapore

Background

In recent years, behaviourally driven policies such as nudges have been increasingly implemented to steer desired outcomes in public health. This study examines the different nudges and the socio-demographic characteristics and lifestyle behaviours that are associated with public acceptance of lifestyle nudges.

Methods

The study used data from the nationwide Knowledge, Attitudes and Practices study (KAP) on diabetes in Singapore. Three types of nudges arranged in increasing order of intrusiveness were examined: (1) information government campaigns, (2) government mandated information and (3) default rules and choice architecture. Acceptance was assessed based upon how much respondents ‘agreed’ with related statements describing heathy lifestyle nudges. Multivariable linear regressions were performed with socio-demographics and lifestyle behaviours using scores calculated for each nudge.

Results

The percentage of respondents who agreed to all statements related to each nudge were: 75.9% (information government campaigns), 73.0% (government mandated information), and 33.4% (default rules and choice architecture). Respondents of Malay/Others ethnicity (vs. Chinese) were more likely to accept information government campaigns. Respondents who were 18 – 34 years old (vs 65 years and above), female, of Malay/Indian ethnicity (vs Chinese), were sufficiently physically active, and with a healthier diet based on the DASH (Dietary Approach to Stop Hypertension) score were more likely to accept nudges related to government mandated information. Respondents of Malay/Indian ethnicity (vs Chinese), and who had a healthier diet were more likely to accept default rules and choice architecture.

Conclusion

Individuals prefer less intrusive approaches for promoting healthy lifestyle. Ethnicity and lifestyle behaviours are associated with acceptance of nudges and should be taken into consideration during the formulation and implementation of behaviourally informed health policies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-13668-x.

A Nudge-Inspired AI-Driven Health Platform for Self-Management of Diabetes

Diabetes mellitus is a serious chronic disease that affects the blood sugar levels in individuals, with current predictions estimating that nearly 578 million people will be affected by diabetes by 2030. Patients with type II diabetes usually follow a self-management regime as directed by a clinician to help regulate their blood glucose levels. Today, various technology solutions exist to support self-management; however, these solutions tend to be independently built, with little to no research or clinical grounding, which has resulted in poor uptake. In this paper, we propose, develop, and implement a nudge-inspired artificial intelligence (AI)-driven health platform for self-management of diabetes. The proposed platform has been co-designed with patients and clinicians, using the adapted 4-cycle design science research methodology (A4C-DSRM) model. The platform includes (a) a cross-platform mobile application for patients that incorporates a macronutrient detection algorithm for meal recognition and nudge-inspired meal logger, and (b) a web-based application for the clinician to support the self-management regime of patients. Further, the platform incorporates behavioral intervention techniques stemming from nudge theory that aim to support and encourage a sustained change in patient lifestyle. Application of the platform has been demonstrated through an illustrative case study via two exemplars. Further, a technical evaluation is conducted to understand the performance of the MDA to meet the personalization requirements of patients with type II diabetes.

Nudging COVID-19 Vaccine Uptake by Changing the Default: A Randomized Controlled Trial

BACKGROUND

Although vaccination against SARS-CoV-2 is considered the central strategy against the pandemic, uptake lags behind target rates.

METHOD

To explore whether this rate could be enhanced by a nudging strategy that exploits the status quo bias, we conducted a randomized controlled trial in northern Italy comparing vaccination acceptance among 2000 adults, ages 50 to 59 years, who were either invited to set an appointment (opt-in group) or assigned an individual appointment (opt-out group).

RESULTS

Results indicate a difference of 3.2 percentage points, which represents a 32% relative increase in the vaccination rate for the opt-out group compared with the opt-in group.

CONCLUSIONS

A significant portion of those who remain unvaccinated may not hold strong beliefs against vaccination but rather tend to inaction and may therefore be nudged toward vaccination with a reduction of action required.

HIGHLIGHTS

Reluctant adults (50-59 years), who had not yet received vaccines against COVID-19, were sent letters announcing appointment availabilityIn an RCT, the status quo option in the notices influenced the rate of vaccine acceptanceNudging via pre-scheduled appointments encouraged vaccine uptake more than invitations to schedule didSwitching the default option yielded a 32% relative increase (13.1% vs. 9.9%) in vaccination.

Development of a Nudge Program at One Alaska Food Pantry

Food pantry clients experience many health disparities, including elevated incidence of diabetes, heart disease, and other nutrition-related conditions. Nutrition education interventions in the form of a nudge can be an effective method to increase nutrition knowledge and healthy pantry food selection. Currently there is no nutrition education program at the largest food pantry in Alaska. The goal of this project was to develop a nutrition intervention in the form of a nudge to increase the selection of nutritious foods by pantry clients. Methods included the development of nudges, or environmental cues, within the pantry as well as client education handouts and recipes for clients to take home. Implications for practice include the potential to increase staff and client knowledge and nutrition education, as well as for impacting the overall health and food security of the clients and their families. Additional implications include the availability of the program and resources for other food pantries across the state to customize for use in their facilities. After the program has been implemented, it can be evaluated across each site and its efficacy determined to implement into policy.

Customer support for nudge strategies to promote fruit and vegetable intake in a university food service

Background

Diverse nudges, also known as choice architectural techniques, have been found to increase fruit and vegetable (FV) selection in both lab and field studies. Such strategies are unlikely to be adopted in mass eating settings without clear evidence of customer support; confirmation in specific contexts is needed. Inspired by the Taxonomy of Choice Architecture, we assessed support for eight types of nudging to increase the choice of FV-rich foods in a university food service. We also explored whether and to what extent nudge support was associated with perceived effectiveness and intrusiveness.

Methods

An online survey was conducted with students who used on-campus cafeterias. Multiple recruitment methods were used. Participants were given 20 specific scenarios for increasing FV selection and asked about their personal support for each nudge, as well as perceived intrusiveness and effectiveness. General beliefs about healthy eating and nudging were also measured. Results were assessed by repeated measures ANOVA for the 8 nudge types.

Results

All nudge scenarios achieved overall favourable ratings, with significant differences among different types of nudging by the 298 respondents. Changing range of options (type B3) and changing option-related consequences (type B4) received the highest support, followed by changing option-related effort (type B2) and making information visible (type A2). Translating information (type A1), changing defaults (type B1) and providing reminders or facilitating commitment (type C) were less popular types of nudging. Providing social reference points (type A3) was least supported. Support for nudge types was positively associated with the belief that food services have a role in promoting healthy eating, perceived importance of FV intake, trustworthiness of the choice architect and female gender. Lastly, support for all types of nudges was positively predicted by perceived effectiveness of each nudge and negatively predicted by perceived intrusiveness above and beyond the contribution of general beliefs about healthy eating and nudging.

Conclusions

Findings from the current study indicate significant differences in support for nudge techniques intended to increase FV selection among university cafeteria users. These findings offer practical implications for food service operators as well as public health researchers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-13054-7.

Are You "Nudgeable"? Factors Affecting the Acceptance of Healthy Eating Nudges in a Cafeteria Setting

Research has identified nudging as a promising and effective tool to improve healthy eating behavior in a cafeteria setting. However, it remains unclear who is and who is not “nudgeable” (susceptible to nudges). An important influencing factor at the individual level is nudge acceptance. While some progress has been made in determining influences on the acceptance of healthy eating nudges, research on how personal characteristics (such as the perception of social norms) affect nudge acceptance remains scarce. We conducted a survey on 1032 university students to assess the acceptance of nine different types of healthy eating nudges in a cafeteria setting with four influential factors (social norms, health-promoting collaboration, responsibility to promote healthy eating, and procrastination). These factors are likely to play a role within a university and a cafeteria setting. The present study showed that key influential factors of nudge acceptance were the perceived responsibility to promote healthy eating and health-promoting collaboration. We also identified three different student clusters with respect to nudge acceptance, demonstrating that not all nudges were accepted equally. In particular, default, salience, and priming nudges were at least moderately accepted regardless of the degree of nudgeability. Our findings provide useful policy implications for nudge development by university, cafeteria, and public health officials. Recommendations are formulated for strengthening the theoretical background of nudge acceptance and the susceptibility to nudges.

Rumination and Worry Selectively Modulate Total Calorie Consumption within an Online, Nudge Tactic Paradigm

Rumination and worry, collectively referred to as perseverative cognition, have been implicated in the increased engagement of several health risk behaviours. The current study aimed to investigate the potential influencing role of these repetitive negative thought cognitions in an online snack paradigm. Participants were randomly assigned to either an even condition (a 3:3 ratio of ≤101 kcal and >201 kcal snacks) or an uneven condition (a 4:2 ratio in favour of ≤101 kcal snacks). Upon the presentation of six images of sweet treats, participants were asked to choose the snack they most wanted to consume “right now”, before completing the Ultra-Brief Penn State Worry Questionnaire (UB-PSWQ) and the brief (5-item) Ruminative Response Scale (RRS). The results showed that the reduced availability of higher calorie snacks significantly improved both snack choice and total calorie consumption. However, despite rumination and worry having no influence on the snack type chosen, higher levels of rumination still led to significantly higher overall calorie consumption. Although, contrary to predictions, higher levels of worry conversely led to significantly lower overall calorie consumption. This study adds to the growing work in the role of perseverative cognition and food consumption, which may aid in informing public health strategies. Further exploration is needed to assess whether rumination directly induces unhealthy eating behaviours or simply exacerbates them.

Nudging food service users to choose fruit- and vegetable-rich items: Five field studies

Although nudging has been found to promote the choice of healthy foods in lab studies and ad-hoc field studies, relatively little research is available regarding effectiveness in real food venues that operate for profit. The paucity of empirical studies providing "proof of implementation" reveals the difficulty of applying previous empirical findings on nudging to mass-eating food services contexts, which serve meals to a lot of individuals daily. Based on the typology of choice architecture in food choice contexts, we closely collaborated with the in-house food service operator to devise and implement five nudge interventions to promote fruits and vegetables (FV) in university cafeterias. Each study was conducted for one 12-week semester or more over a three-year period. In the first two studies, non-verbal point-of-purchase prompting increased the choice of kale/spinach supplemented smoothies and whole fruits from baskets. In Study 3, the combination of sizing and point-of-purchase non-verbal prompting increased the sale of large size vegetable-rich bowls from a stir-fry grill. In Study 4, the proximity type of nudging by altering the position of the healthier option in a sandwich bar in combination with non-verbal prompting increased the sale of sandwiches containing spinach. In Study 5, the combination of sizing and proximity of large vs. small sized plates and serving spoons had no effect on sale of self-serve items in a salad bar. All the interventions except for Study 5 produced a moderate effect in increasing the choice of FV-rich items. We recommend that hospitality and food service operators consider operational parameters and simultaneously adopt more than one nudging components to achieve a sizable effect. Future randomized controlled trials are needed to implement choice architecture techniques in collaboration with food service companies.

Effectiveness of Digital Forced-Choice Nudges for Voluntary Data Donation by Health Self-trackers in Germany: Web-Based Experiment

BACKGROUND

Health self-tracking is an evidence-based approach to optimize health and well-being for personal self-improvement through lifestyle changes. At the same time, user-generated health-related data can be of particular value for (health care) research. As longitudinal data, these data can provide evidence for developing better and new medications, diagnosing rare diseases faster, or treating chronic diseases.

OBJECTIVE

This quantitative study aims to investigate the impact of digital forced-choice nudges on the willingness of German health self-trackers to donate self-tracked health-related data for research. This study contributes to the body of knowledge on the effectiveness of nonmonetary incentives. Our study enables a gender-specific statement on influencing factors on the voluntary donation of personal health data and, at the same time, on the effectiveness of digital forced-choice nudges within tracking apps.

METHODS

We implemented a digital experiment using a web-based questionnaire by graphical manipulation of the Runtastic tracking app interface. We asked 5 groups independently to indicate their willingness to donate tracked data for research. We used a digital forced-choice nudge via a pop-up window, which framed the data donation request with 4 different counter values. We generated the counter values according to the specific target group needs identified from the research literature.

RESULTS

A sample of 919 was generated, of which, 625 (68%) were women and 294 (32%) were men. By dividing the sample into male and female participants, we take into account research on gender differences in privacy tendencies on the web and offline, showing that female participants display higher privacy concerns than male participants. A statistical group comparison shows that with a small effect size (r=0.21), men are significantly more likely (P=.04) to donate their self-tracked data for research if the need to take on social responsibility is addressed (the prosocial counter value in this case-contributing to society) compared with the control group without counter value. Selfish or pseudoprosocial counter values had no significant effect on willingness to donate health data among male or female health self-trackers in Germany when presented as a forced-choice nudge within a tracking app.

CONCLUSIONS

Although surveys regularly reveal an 80% to 95% willingness to donate data on average in the population, our results show that only 41% (377/919) of the health self-trackers would donate their self-collected health data to research. Although selfish motives do not significantly influence willingness to donate, linking data donation to added societal value could significantly increase the likelihood of donating among male self-trackers by 15.5%. Thus, addressing the need to contribute to society promotes the willingness to donate data among male health self-trackers. The implementation of forced-choice framing nudges within tracking apps presented in a pop-up window can add to the accessibility of user-generated health-related data for research.

A Brief Media Intervention Influences Collegiate Males' Attitude and Knowledge Towards Breastfeeding

Breastfeeding is the optimal source of infant nutrition, yet the mother's decision to breastfeed is complex and influenced by factors including social support and breastfeeding knowledge and attitudes. This study employed a two-group pretest-posttest design to examine whether brief, online video presentations (<2.5 minutes in length) could improve breastfeeding knowledge and attitude among males and compare the outcomes between a knowledge-based and attitude-based intervention. Collegiate male participants (N = 213, 18-40 years of age) demonstrated high breastfeeding exposure (90.1% had friends/family breastfeed) and positive attitudes (89.2% accepted women could breastfeed and work outside home) yet knowledge deficits concerning breastfeeding health benefits were identified. Breastfeeding exposure was positively associated with baseline attitude (r(212)=.186, p = .006 and knowledge (r(212)=.229, p = .001. Both intervention groups reported similar gains in attitude scores; only the knowledge-based intervention reported significant gains in knowledge (M = 1.5, SD = 2.63 vs M = -.07, SD = 1.44, (t = -5.496, df = 211, p < .05). Brief online video presentations may constitute an additional exposure to or nudging toward breastfeeding, and breastfeeding knowledge and attitudes can be positively influenced in young adult males with similar interventions that are affordable and require a minimal time commitment.

The El Valor de Nuestra Salud clustered randomized controlled trial store-based intervention to promote fruit and vegetable purchasing and consumption

Background

Modifying the environment to promote healthy foods is a population-based approach for improving diet. This study evaluated the outcome effectiveness of a food store intervention that used structural and social change strategies to promote fruits and vegetables. It was hypothesized that intervention versus control store customers would improve their consumption of fruits and vegetables at 6 months.

Trial design

Clustered randomized controlled trial

Methods

Sixteen pair-matched stores were randomized to an intervention or wait-list control condition. With the research team’s support, intervention stores modified the availability, accessibility, and promotion of fruits and vegetables, including augmenting produce displays within the store and building employees’ capacity to place and promote fruits and vegetables throughout the store (Phase 1), followed by the delivery of a customer-directed marketing campaign for 6 months (Phase 2). From months 7 to 12, stores were encouraged to maintain strategies on their own (Phase 3). Customer-reported daily fruit and vegetable consumption (cups/day) were collected by blinded research assistants at three time-points (baseline, 6 months and 12 months post-baseline) from 369 participating customers (an average of 23/store). Secondary outcomes included customer-reported fruit and vegetable purchasing and other behaviors.

Results

The study retained the 16 stores and most customers at 6 (91%) and 12 (89%) months. Although significant differences were not observed in the overall sample for vegetable consumption, male customers of intervention versus control stores consumed significantly more fruit daily at 6 months [mean (standard deviation) cups at baseline and six months; intervention: 1.6 (1.5) to 1.6 (1.5) vs. control: 1.4 (1.2) to 1.1 (0.8)]. However, this difference was not observed at 12 months, or among females. There was an overall increase in dollars spent at the targeted store in the intervention versus control condition among male versus female customers at 6 months; however, no change was observed in the percent of dollars spent on fruits and vegetables at the targeted store. Frequency of shopping at the targeted store did not modify intervention effects.

Conclusions

Structural and social change interventions can modify customers’ behavior in the short-term. Future research should consider methods for achieving longer-term changes, and potential generalizability to other products (e.g., energy-dense sweet and savory products).

Trial registration

NCT01475526

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-021-01220-w.

Online Pilot Grocery Intervention among Rural and Urban Residents Aimed to Improve Purchasing Habits

Online grocery shopping has the potential to improve access to food, particularly among low-income households located in urban food deserts and rural communities. The primary aim of this pilot intervention was to test whether a three-armed online grocery trial improved fruit and vegetable (F&V) purchases. Rural and urban adults across seven counties in Kentucky, Maryland, and North Carolina were recruited to participate in an 8-week intervention in fall 2021. A total of 184 adults were enrolled into the following groups: (1) brick-and-mortar "BM" (control participants only received reminders to submit weekly grocery shopping receipts); (2) online-only with no support "O" (participants received weekly reminders to grocery shop online and to submit itemized receipts); and (3) online shopping with intervention nudges "O+I" (participants received nudges three times per week to grocery shop online, meal ideas, recipes, Facebook group support, and weekly reminders to shop online and to submit itemized receipts). On average, reported food spending on F/V by the O+I participants was USD 6.84 more compared to the BM arm. Online shopping with behavioral nudges and nutrition information shows great promise for helping customers in diverse locations to navigate the increasing presence of online grocery shopping platforms and to improve F&V purchases.

Digital Nudging for Online Food Choices

When people search for what to cook for the day, they increasingly use online recipe sites to find inspiration. Such recipe sites often show popular recipes to make it easier to find a suitable choice. However, these popular recipes are not always the healthiest options and can promote an unhealthy lifestyle. Our goal is to understand to what extent it is possible to steer the food selection of people through digital nudging. While nudges have been shown to affect humans' behavior regarding food choices in the physical world, there is little research on the impact of nudges on online food choices. Specifically, it is unclear how different nudges impact (i) the behavior of people, (ii) the time they need to make a decision, and (iii) their satisfaction and confidence with their selection. We investigate the effects of highlighting, defaults, social information, and warnings on the decision-making of online users through two consecutive user studies. Our results show that a hybrid nudge, which both involves setting a default and adding social information, significantly increases the likelihood that a nudged item is selected. Moreover, it may help decreasing the required decision time for participants while having no negative effects on the participant's satisfaction and confidence. Overall, our work provides evidence that nudges can be effective in this domain, but also that the type of a digital nudge matters. Therefore, different nudges should be evaluated in practical applications.

How community participation in water and sanitation interventions impacts human health, WASH infrastructure and service longevity in low-income and middle-income countries: a realist review

OBJECTIVE

To understand how, and under what circumstances community participation in water and sanitation interventions impacts the availability of safe water and sanitation, a change in health status or behaviour and the longevity of water, sanitation and hygiene (WASH) resources and services.

DESIGN

Realist review.

DATA SOURCES

PubMed, Web of Science and Scopus databases were used to identify papers from low-income and middle-income countries from 2010 to 2020.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Criteria were developed for papers to be included. The contribution of each paper was assessed based on its relevance and rigour (eg, can it contribute to context, mechanism or outcome, and is the method used to generate that information credible).

ANALYSIS

Inductive and deductive coding was used to generate context-mechanism-outcome configurations.

RESULTS

73 studies conducted in 29 countries were included. We identified five mechanisms that explained the availability, change and longevity outcomes: (1) accountability (policies and procedures to hold communities responsible for their actions and outcomes of an intervention), (2) diffusion (spread of an idea or behaviour by innovators over time through communication among members of a community), (3) market (the interplay between demand and supply of a WASH service or resource), (4) ownership (a sense of possession and control of the WASH service or resource) and (5) shame (a feeling of disgust in one's behaviour or actions). Contextual elements identified included community leadership and communication, technical skills and knowledge, resource access and dependency, committee activity such as the rules and management plans, location and the level of community participation.

CONCLUSIONS

The findings highlight five key mechanisms impacted by 19 contextual factors that explain the outcomes of community water and sanitation interventions. Policymakers, programme implementers and institutions should consider community dynamics, location, resources, committee activity and practices and nature of community participation, before introducing community water and sanitation interventions.

The nudge strategies for weight loss in adults with obesity and overweight: A systematic review and meta-analysis

Obesity and overweight conditions have become major health challenges worldwide. The exploration of effective weight loss strategies is essential. Nudges are currently advancing approaches that represent a new and better method for changing the behaviors of people. However, the effectiveness of nudge interventions on weight loss in overweight people who may be obese has not been synthesized in a systematic manner. In this study, a systematic literature search was performed. Only randomized controlled trials (RCTs) were considered. Weighted mean differences (WMDs) and 95% confidence intervals (CIs) were calculated as summary statistics. In total, 25 RCTs involving a population of 5,929 individuals were included. Significant effects of the nudge strategy on weight loss (WMD: -0.96 kg, 95% CI: -1.49 to -0.43), body mass index (WMD: -0.3 kg/m², 95% CI: -0.41 to -0.19) and waist circumference (WMD: -0.75 cm, 95% CI: -1.23 to -0.27) were observed. The subgroup analysis showed that the reduction in body weight associated with nudge interventions was significant in younger and more obese people. Moreover, the effect of nudge intervention on weight loss weakened over time. Overall, the nudge strategy can promote changes in weight loss, body mass index and waist circumference of adults, albeit at a mild magnitude and in particular types of individuals. Nudge strategies can be recommended to clinical practitioners and policy-makers to promote obesity management.

Nudge strategies for behavior-based prevention and control of neglected tropical diseases: A scoping review and ethical assessment

Background

Nudging, a strategy that uses subtle stimuli to direct people’s behavior, has recently been included as an effective and low-cost behavior change strategy in low- and middle- income countries (LMIC), targeting behavior-based prevention and control of neglected tropical diseases (NTDs). The present scoping review aims to provide a timely overview of how nudge interventions have been applied within this field. In addition, the review proposes a framework for the ethical consideration of nudges for NTD prevention and control, or more broadly global health promotion.

Methods

A comprehensive search was performed in several databases: MEDLINE, PsycINFO, and Embase (Ovid), Web of Science Core Collection, CINAHL, ERIC and Econ.Lit (EBSCO), as well as registered trials and reviews in CENTRAL and PROSPERO to identify ongoing or unpublished studies. Additionally, studies were included through a handpicked search on websites of governmental nudge units and global health or development organizations.

Results

This scoping review identified 33 relevant studies, with only two studies targeting NTDs in particular, resulting in a total of 67 nudge strategies. Most nudges targeted handwashing behavior and were focused on general health practices rather than targeting a specific disease. The most common nudge strategies were those targeting decision assistance, such as facilitating commitment and reminder actions. The majority of nudges were of moderate to high ethical standards, with the highest standards being those that had the most immediate and significant health benefits, and those implemented by agents in a trust relationship with the target audience.

Conclusion

Three key recommendations should inform research investigating nudge strategies in global health promotion in general. Firstly, future efforts should investigate the different opportunities that nudges present for targeting NTDs in particular, rather than relying solely on integrated health promotion approaches. Secondly, to apply robust study designs including rigorous process and impact evaluation which allow for a better understanding of ‘what works’ and ‘how it works’. Finally, to consider the ethical implications of implementing nudge strategies, specifically in LMIC.

Behavior is at the core of neglected tropical disease (NTD) prevention and control, certainly within low-, and middle- income countries (LMIC) where resources are often limited. Therefore, strategies to promote behavior change should be included and investigated in future efforts. Nudging, a low-cost strategy that subtly directs people towards positive behavioral choices, has recently gained attention in global health promotion. Nudge strategies have been applied to a wide range of health-promoting behaviors such as handwashing. To understand which strategies were used, where and how these were applied, and whether these were ethically informed and implemented, we undertook a comprehensive review of the available sources. This resulted in 33 included studies, with a total of 67 nudge strategies for behavior-based prevention and control of NTDs in LMIC. Only two studies targeted NTDs in particular, the other 31 included studies were focused on more general health promoting behaviors, with the majority targeting handwashing with soap. The most common nudge strategies were those targeting decision assistance, such as fostering commitment and reminder actions. In general, the ethical assessment presented favorable results. We identified the need for robust study designs to better understand how nudges can be implemented in the future.

Testosterone and cortisol are more predictive of choice behavior than a social nudge in adult males on a simple gift give-get task

Reproducibility of social research is ambitious, and evidence supporting this argument is increasing in psychology and social science research. This may be attributed to, in part, the high volume of qualitative research methodology used in social research along with difficulties in the reliability of measurement techniques. Therefore, use of more and better objective measures to complement existing techniques in social research are necessitated. To highlight this point we explored the success of give-get nudge in adults. Nudge being a subtle intervention to influence choice, without restricting choice. We also wanted to explore whether testosterone and cortisol, as objective psychophysiological markers, could explain nudge outcome. Participants were asked what they would like to get for Christmas, or what they would like to give. They were then presented with two chocolates, one big and one small, and instructed to take as a "reward" for their participation with the knowledge there was one other participant to take chocolate after them. It was hypothesized that those asked to give something for Christmas would take the smaller reward and vice versa. Salivary testosterone and cortisol were measured prior to, and 10 min after completing the exercise. The nature of the nudge itself did not predict behavior, but the hormone measures did. We speculate that testosterone may focus an individual on the nature of the question (nudge), while cortisol encourages self-focus. These results support the need to combine existing social research techniques with more objective markers.

Nudging toward vaccination: a systematic review

Background

Vaccine hesitancy (VH) and the global decline of vaccine coverage are a major global health threat, and novel approaches for increasing vaccine confidence and uptake are urgently needed. ‘Nudging’, defined as altering the environmental context in which a decision is made or a certain behaviour is enacted, has shown promising results in several health promotion strategies. We present a comprehensive synthesis of evidence regarding the value and impact of nudges to address VH.

Methods

We conducted a systematic review to determine if nudging can mitigate VH and improve vaccine uptake. Our search strategy used Medical Subject Headings (MeSH) and non-MeSH terms to identify articles related to nudging and vaccination in nine research databases. 15 177 titles were extracted and assessed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The final list of included articles was evaluated using the Mixed Methods Appraisal Tool and the Grading of Recommendations, Assessment, Development and Evaluations framework.

Findings

Identified interventions are presented according to a framework for behaviour change, MINDSPACE. Articles (n=48) from 10 primarily high-income countries were included in the review. Nudging-based interventions identified include using reminders and recall, changing the way information is framed and delivered to an intended audience, changing the messenger delivering information, invoking social norms and emotional affect (eg, through storytelling, dramatic narratives and graphical presentations), and offering incentives or changing defaults. The most promising evidence exists for nudges that offer incentives to parents and healthcare workers, that make information more salient or that use trusted messengers to deliver information. The effectiveness of nudging interventions and the direction of the effect varies substantially by context. Evidence for some approaches is mixed, highlighting a need for further research, including how successful interventions can be adapted across settings.

Conclusion

Nudging-based interventions show potential to increase vaccine confidence and uptake, but further evidence is needed for the development of clear recommendations. The ongoing COVID-19 pandemic increases the urgency of undertaking nudging-focused research.

PROSPERO registration number

CRD42020185817.

Nudging healthy college dining hall choices using behavioral economics

To apply behavioral economics strategies (i.e., placement changes and signage) to nudge university students' healthy dining hall eating. Participants: A convenience sample of 4208 students exiting a university dining hall were asked to take a brief survey on meal selections. Methods: Three unique nudges (related to beverage, snack and dessert) were individually introduced and then removed for a week using a quasi-experimental design. Exit surveys during non-nudge and intervention periods were compared using chi-square analysis. Results: The beverage nudge significantly increased water consumption (p=.03) and the dessert nudge significantly increased healthy dessert consumption (p<.001) between comparison and intervention weeks. The snack intervention did not significantly affect snack choice. Conclusions: Simple signage interventions may be effective to encourage healthy eating behaviors in a college dining hall setting. Student health may be improved by nudging students to select healthier beverage and dessert options.

Post-Secondary Food Service Manager Perspectives on Fruit and Vegetable Nudging Strategies: Qualitative Study

BACKGROUND

Changing the choice architecture in post-secondary food service contexts to "nudge" customers to choose more fruits and vegetables (FV) shows promise in intervention studies to date. If such approaches are to become more widely adopted, they must be feasible and acceptable to food service managers. Among possible early adopters, managers of food services in post-secondary education institutions may have unique insights on implementation of such approaches, as they have dual mandates to support student health and maintain profitability.

OBJECTIVE

The goal of this exploratory study was to examine current knowledge, practice, facilitators, and barriers to uptake of nudge strategies promoting FV in a sample of post-secondary food service managers.

METHODS

A qualitative telephone interview study was undertaken with food service managers across Canada (n = 10 institutions), recruited from a national professional organization. One or more representatives from each institution completed the interview. Interviews were audio-recorded, transcribed, and underwent framework descriptive and interpretative content analysis in NVivo (QSR International). Münscher's Taxonomy of Choice Architecture and the Ottawa Model for Research Use guided development and analysis.

RESULTS

Managers from 9 universities and 1 technical college participated. Local context, governance, and resources varied widely. Eight of 10 institutions used some form of FV nudging as part of their marketing and health promotion, most commonly to reduce the effort associated with choosing FV. Nudging strategies aimed at increasing the range and composition of FV offerings, providing a social reference (opinion leaders) for choosing FV, and changing consequences with loyalty cards were also common. Other nudging strategies were used infrequently. Cost, operational ease of implementation, and students' privacy and choices were critical issues in adoption.

CONCLUSIONS

The results can inform development and testing of locally adapted nudge interventions. It is critical that managers be involved from the outset of any planned academic implementation study.

Dilemmas of nudging in public health: an ethical analysis of a Danish pamphlet

Nudging has been discussed in the context of public health, and ethical issues raised by nudging in public health contexts have been highlighted. In this article, we first identify types of nudging approaches and techniques that have been used in screening programmes, and ethical issues that have been associated with nudging: paternalism, limited autonomy and manipulation. We then identify nudging techniques used in a pamphlet developed for the Danish National Screening Program for Colorectal Cancer. These include framing, default nudge, use of hassle bias, authority nudge and priming. The pamphlet and the very offering of a screening programme can in themselves be considered nudges. Whether nudging strategies are ethically problematic depend on whether they are categorized as educative- or non-educative nudges. Educative nudges seek to affect people's choice making by engaging their reflective capabilities. Non-educative nudges work by circumventing people's reflective capabilities. Information materials are, on the face of it, meant to engage citizens' reflective capacities. Recipients are likely to receive information materials with this expectation, and thus not expect to be affected in other ways. Non-educative nudges may therefore be particularly problematic in the context of information on screening, also as participating in screening does not always benefit the individual.

The effect of nudges on autonomy in hypothetical and real life settings

Nudges have repeatedly been found to be effective, however they are claimed to harm autonomy, and it has been found that laypeople expect this too. To test whether these expectations translate to actual harm to experienced autonomy, three online studies were conducted. The paradigm used in all studies was that participants were asked to voluntarily participate in a longer version of the questionnaire. This was either done in a hypothetical setting, where participants imagined they were asked this question, but did not answer it, and reported their expectations for autonomy; Or in an actual choice setting where participants answered the question and then reported their actual autonomy. The first study utilized the hypothetical setting and tried to replicate that laypeople expect nudges to harm autonomy with the current paradigm. A total of 451 participants were randomly assigned to either a control, a default nudge, or a social norm nudge condition. In the default nudge condition, the affirmative answer was pre-selected, and in the social norm nudge condition it was stated that most people answered affirmative. The results showed a trend for lower expected autonomy in nudge conditions, but did not find significant evidence. In Study 2, with a sample size of 454, the same design was used in an actual choice setting. Only the default nudge was found to be effective, and no difference in autonomy was found. In Study 3, Studies 1 and 2 were replicated. Explanation of the nudge was added as an independent variable and the social norm nudge condition was dropped, resulting in six conditions and 1322 participants. The results showed that participants indeed expected default nudges to harm their autonomy, but only if the nudge was explained. When actually nudged, no effect on autonomy was found, independent of the presence of an explanation.

A model of integrated remote monitoring and behaviour change for osteoarthritis

Background

The National Institute for Health and Care Excellence recommends the use of digital and mobile health technologies to facilitate behaviour change interventions. Due to its high prevalence and dependence upon patient self-management strategies, osteoarthritis is one musculoskeletal condition which may benefit from such approaches. This is particularly pertinent due to the increasing use of remote monitoring technologies to collect patient data and facilitate self-management in individuals outside of hospital clinics. In practice however, application of digital behaviour change interventions is difficult due to insufficient reporting of behaviour change theories in the current literature. When digital technologies are employed to alter behaviour change in osteoarthritis, they often focus on physical activity. Currently, such interventions focus of self-efficacy but do not often explicitly report the behaviour change techniques they use to facilitate these changes.

Methods

This paper proposes a new model of integrating specific behaviour change principles (persuasive design) in an integrated model of remote monitoring and digital behaviour change interventions for osteoarthritis.

Results

There is potential to combine remote monitoring systems of patient data through digital and mobile technologies with behaviour change principles to improve physical activity behaviours in individuals with osteoarthritis. The use of persuasive design principles (e.g. prompts or nudges) through mobile notifications and strategic system design can be directed to enhance behaviour change. A validated measure of behaviour change, such as the patient activation measure, will allow effective evaluation of such systems.

Conclusions

Digital behaviour change interventions should be directed towards the underlying principles of behaviour change they employ, although this is not commonly reported in practice. Such interventions can be integrated within remote monitoring pathways using persuasive design techniques to enhance patient activation. This approach can enhance self-management in individuals with musculoskeletal conditions, such as osteoarthritis.

Equity Effects of Dietary Nudging Field Experiments: Systematic Review

Background: Dietary behaviours are among the key modifiable risk factors for non-communicable diseases. Importantly, dietary behaviours vary substantially between groups and individuals with different socioeconomic positions, with more disadvantaged groups and individuals being exposed to more dietary risk factors. The goal of this review is to summarise the existing research on equity effects of dietary nudging interventions. Methods: Systematic review of nudging interventions conducted in a field setting that report an observable indicator of dietary behaviour, include a control group, and report effect sizes stratified by indicators of socioeconomic status as outlined in the PROGRESS-Plus framework. Two databases (scopus, Pubmed) were searched (last search June 2021), and 18 articles with 19 studies (k = 46 equity comparisons) were included. Risk of bias was assessed using the ROBINS-I tool. Due to heterogeneity in equity dimensions and study outcomes, a harvest plot was used to summarise data. Results: The majority of equity comparisons (38 out of 46) were available for cognitive nudges. Most of these (22 out of 38 comparisons) found that cognitive nudges worked equally well in more and less disadvantaged populations; however, in 12 out of the 38 comparisons, they favoured those who were less disadvantaged. Two out of four comparisons on behavioural nudges favoured more disadvantaged persons. Conclusions: The differential effects of dietary nudging interventions in this review can contribute to increases in health inequalities. At the same time, a substantial number of interventions showed no equity effects. Importantly, this review suggests that more research on nudging interventions and health equity is needed. Future interventions should report effect sizes stratified by indicators of social inequality. Systematic Review Registration: PROSPERO (CRD42019137469).

Systematic review of clinician-directed nudges in healthcare contexts

OBJECTIVE

Nudges are interventions that alter the way options are presented, enabling individuals to more easily select the best option. Health systems and researchers have tested nudges to shape clinician decision-making with the aim of improving healthcare service delivery. We aimed to systematically study the use and effectiveness of nudges designed to improve clinicians' decisions in healthcare settings.

DESIGN

A systematic review was conducted to collect and consolidate results from studies testing nudges and to determine whether nudges directed at improving clinical decisions in healthcare settings across clinician types were effective. We systematically searched seven databases (EBSCO MegaFILE, EconLit, Embase, PsycINFO, PubMed, Scopus and Web of Science) and used a snowball sampling technique to identify peer-reviewed published studies available between 1 January 1984 and 22 April 2020. Eligible studies were critically appraised and narratively synthesised. We categorised nudges according to a taxonomy derived from the Nuffield Council on Bioethics. Included studies were appraised using the Cochrane Risk of Bias Assessment Tool.

RESULTS

We screened 3608 studies and 39 studies met our criteria. The majority of the studies (90%) were conducted in the USA and 36% were randomised controlled trials. The most commonly studied nudge intervention (46%) framed information for clinicians, often through peer comparison feedback. Nudges that guided clinical decisions through default options or by enabling choice were also frequently studied (31%). Information framing, default and enabling choice nudges showed promise, whereas the effectiveness of other nudge types was mixed. Given the inclusion of non-experimental designs, only a small portion of studies were at minimal risk of bias (33%) across all Cochrane criteria.

CONCLUSIONS

Nudges that frame information, change default options or enable choice are frequently studied and show promise in improving clinical decision-making. Future work should examine how nudges compare to non-nudge interventions (eg, policy interventions) in improving healthcare.

Meta-regression methods to characterize evidence strength using meaningful-effect percentages conditional on study characteristics

Meta-regression analyses usually focus on estimating and testing differences in average effect sizes between individual levels of each meta-regression covariate in turn. These metrics are useful but have limitations: they consider each covariate individually, rather than in combination, and they characterize only the mean of a potentially heterogeneous distribution of effects. We propose additional metrics that address both limitations. Given a chosen threshold representing a meaningfully strong effect size, these metrics address the questions: "For a given joint level of the covariates, what percentage of the population effects are meaningfully strong?" and "For any two joint levels of the covariates, what is the difference between these percentages of meaningfully strong effects?" We provide semiparametric methods for estimation and inference and assess their performance in a simulation study. We apply the proposed methods to meta-regression analyses on memory consolidation and on dietary behavior interventions, illustrating how the methods can provide more information than standard reporting alone. To facilitate implementing the methods in practice, we provide reporting guidelines and simple R code.

The impact of food packaging on measured food intake: A systematic review of experimental, field and naturalistic studies

Chronic, excess energy intake contributes to overweight and obesity. Solutions are needed to guide consumers towards portion control, especially for high energy density (HED), palatable foods. Food packaging, a key element of the eating environment, offers a potential solution. To investigate whether packaging design influences measured food intake, a systematic search was undertaken in four electronic databases (Ovid Medline; Ovid PsycInfo; Ovid Embase and Web of Science) across the previous decade. This process yielded 1671 discrete papers, of which 23 articles containing 40 relevant studies were retrieved. Most (n = 36) of the manipulated packaging features influenced consumption quantity with the largest effect sizes observed for packaging which guided consumers either by on-pack cues or structural features. For example, images on the front of the pack, packaging size, as well as partitioning and resealability all helped to reduce food intake. However, individual differences and attentional focus mediate packaging effects. Overall, packaging features can help to limit intake of HED foods and increase intake of nutrient-dense foods (e.g., carrots). Future studies on packaging for portion control (downsizing) might benefit from long term, randomised control trials to test effects outside of the laboratory context and applied to everyday consumer usage.

A cross-sectional study clarifying profiles of patients with diabetes who discontinued pharmacotherapy: reasons and consequences

BACKGROUND

Although diabetes is one of the fastest increasing diseases in prevalence worldwide and demands significant medical resources, more than half of all patients with diabetes do not achieve the expected target level of blood glucose. As a potential cause of poor glycemic control, insufficient adherence to medication has long been discussed and variably studied. However, dropout from treatment as another plausible cause has not been fully examined. The aim of this study was to clarify profiles of patients with diabetes who discontinued pharmacotherapy (Discont group) by extracting reasons of their decisions and by comparing with those who continued (Cont group) in terms of the related factors to glycemic control.

METHODS

A cross-sectional, internet-based survey was conducted among Japanese with diabetes registered in a database. A self-administered questionnaire consisting of the 8-item version of the Morisky Medication Adherence Scale (MMAS-8), glycosylated haemoglobin (HbA_1c) level, and demographic and disease characteristics was completed by all participants. Reasons for medication discontinuation and resumption were also received retrospectively from participants in the Discont group. To examine the risk of uncontrolled HbA_1c, logistic regression analysis was conducted in each group.

RESULTS

In the Discont group (148 cases), older age at resumption of pharmacotherapy and current smoking habit increased the probability of uncontrolled HbA_1c, whereas in the Cont group (146 cases), a familial history of diabetes and better medication adherence in MMAS-8 scores decreased the probability of uncontrolled HbA1c. A relationship between medication adherence and HbA_1c level was seen in the Cont but not in the Discont group. About 70 % of those in the Discont group made their decision to terminate diabetes treatment without consulting physicians and half of them perceived their situations inappropriately.

CONCLUSIONS

Those who discontinued pharmacotherapy were less adherent to medication than those who did not discontinue. Risk factors for glycemic control also differed between those who discontinued and those who did not. More than one-third of participants with diabetes who discontinued pharmacotherapy had inappropriate perceptions of their disease, which medical professionals should be aware of for better interventions.

Determinants of Food Choice and Perceptions of Supermarket-Based Nudging Interventions among Adults with Low Socioeconomic Position: The SUPREME NUDGE Project

Nudging has received ample attention in scientific literature as an environmental strategy to promote healthy diets, and may be effective for reaching populations with low socioeconomic position (SEP). Therefore, the objective of this study was to investigate how the determinants of food choice shape the perceptions regarding supermarket-based nudging strategies among adults with low SEP. We conducted semi-structured interviews among fifteen adults with low SEP using a pre-defined topic list and visual examples of nudges. Interviews were recorded and transcribed verbatim and content analysis was used to analyse the data. The results show that food costs, convenience, healthiness, taste, and habits were frequently mentioned as determinants of food choice. However, the relative importance of these determinants seemed to be context-dependent. Interviewees generally had a positive attitude towards nudges, especially when they were aligned with product preferences, information needs, and beliefs about the food environment. Still, some interviewees also expressed distrust towards nudging strategies, suspecting ulterior motives. We conclude that nudging strategies should target foods which align with product preferences and information needs. However, the suspicion of ulterior motives highlights an important concern which should be considered when implementing supermarket-based nudging strategies.

Interventions to reduce meat consumption by appealing to animal welfare: Meta-analysis and evidence-based recommendations

Reducing meat consumption may improve human health, curb environmental damage, and limit the large-scale suffering of animals raised in factory farms. Most attention to reducing consumption has focused on restructuring environments where foods are chosen or on making health or environmental appeals. However, psychological theory suggests that interventions appealing to animal welfare concerns might operate on distinct, potent pathways. We conducted a systematic review and meta-analysis evaluating the effectiveness of these interventions. We searched eight academic databases and extensively searched grey literature. We meta-analyzed 100 studies assessing interventions designed to reduce meat consumption or purchase by mentioning or portraying farm animals, that measured behavioral or self-reported outcomes related to meat consumption, purchase, or related intentions, and that had a control condition. The interventions consistently reduced meat consumption, purchase, or related intentions at least in the short term with meaningfully large effects (meta-analytic mean risk ratio [RR] = 1.22; 95% CI: [1.13, 1.33]). We estimated that a large majority of population effect sizes (71%; 95% CI: [59%, 80%]) were stronger than RR = 1.1 and that few were in the unintended direction. Via meta-regression, we identified some specific characteristics of studies and interventions that were associated with effect size. Risk-of-bias assessments identified both methodological strengths and limitations of this literature; however, results did not differ meaningfully in sensitivity analyses retaining only studies at the lowest risk of bias. Evidence of publication bias was not apparent. In conclusion, animal welfare interventions preliminarily appear effective in these typically short-term studies of primarily self-reported outcomes. Future research should use direct behavioral outcomes that minimize the potential for social desirability bias and are measured over long-term follow-up.

Eating in the Amazon: Nutritional Status of the Riverine Populations and Possible Nudge Interventions

The Amazon is the largest tropical forest in the world and a source of healthy food, such as fruits and fish. Surprisingly, the Amazonian riverine population present an increased prevalence (as high as 58%) of non-communicable diseases, such as hypertension and insulin resistance, even higher than that described for the urban population of the Amazon. Therefore, this work aimed to analyze the nutritional status and associated risk of the riverine population. Body mass index, waist circumference (WC), waist-to-hip ratio, and neck circumference (NC) were evaluated, and risk analysis was assayed. Furthermore, data about occupation and the prevalence of consumers of the different groups of food were analyzed. All anthropometric parameters revealed high proportions of individuals at risk, WC and NC being the factors that had more high-risk women and men, respectively. Our data confirmed the characteristic profile of the riverine communities with a high number of fish consumers, but also observed different patterns probably associated to a phenomenon of nutrition transition. Based on our data, some nudge interventions that take into account the principles of behavior analysis are discussed and proposed for these populations, aiming to improve the nutritional status and avoid the long-term consequences of the results showed by this work.

Interventions to change purchasing behaviour in supermarkets: a systematic review and intervention content analysis

This systematic review and intervention content analysis used behavioural science frameworks to characterise content and function of interventions targeting supermarket shoppers' purchasing behaviour, and explore if coherence between content and function was linked to intervention effectiveness. Study eligibility: in-store interventions (physical supermarkets) with control conditions, targeting objectively measured food and/or non-alcoholic drink purchases, published in English (no date restrictions). Eleven electronic databases were searched; reference lists of systematic reviews were hand-searched. Methodological quality was assessed using the GATE checklist. A content analysis was performed to characterise intervention content and function, and theoretical coherence between these, using the Behaviour Change Wheel, Behaviour Change Techniques Taxonomy, and Typology of Interventions in Proximal Physical Micro-Environments (TIPPME). Forty-six articles (49 interventions) met inclusion criteria; 26 articles (32 interventions) were included in the content analysis. Twenty behaviour change techniques (BCTs), and four TIPPME intervention types were identified; three BCTs ('Prompts/cues', 'Material incentive', and 'Material reward') were more common in effective interventions. Nineteen interventions solely employed theoretically appropriate BCTs. Theoretical coherence between BCTs and intervention functions was more common in effective interventions. Effective interventions included price promotions and/or in-store merchandising. Future research should explore the effect of specific BCTs using factorial study designs. PROSPERO Registration: CRD42017071065.

Efficiency of In-Store Interventions to Impact Customers to Purchase Healthier Food and Beverage Products in Real-Life Grocery Stores: A Systematic Review and Meta-Analysis

Grocery stores are important settings to promote healthier food and beverage choices. The present paper aims at reviewing the effectiveness of different types of in-store interventions and how they impact sales of different product category in real grocery stores. Systematic search was conducted in six databases. In-store interventions were categorized according to the framework by Kraak et al. (2017) into one or more of eight interventions (e.g., place, profile, portion, pricing, promotion, healthy default picks, prompting and proximity). This systematic theme-based review follows the preferred reporting items for systematic reviews and meta-analyses (PRISMA) data screening and selection. Thirty-six studies were included in the qualitative synthesis and 30 studies were included in the meta-analysis, representing 72 combinations of in-store interventions. The analysis demonstrates that interventions overall had small significant effect size (ES) using Cohen's d on food purchase behavior (d = 0.17, 95% CI [0.04, 0.09]), with largest ES for pricing (d = 0.21) and targeting fruits and vegetables (d = 0.28). Analysis of ES of in-store interventions show that pricing, and pricing combined with promotion and prompting, effectively impacted purchase behavior. Interventions significantly impacted both sales of healthy and unhealthy products and significantly increased sales of fruits and vegetables, healthy beverage and total volume of healthy products. Results should however be interpreted with some caution, given the relatively low quality of overall evidence and low number of studies and observations for some types of intervention. Further research exploring impact on different in-store interventions and targeting especially unhealthy products are needed.

Identifying nudge strategies for behavior-based prevention and control of neglected tropical diseases: a scoping review protocol

OBJECTIVE

The aim of this scoping review is to synthesize the existing body of studies that use nudge strategy and focus on behavioral practices suitable for prevention and control of neglected tropical diseases. The review will map the existing literature, identify gaps in knowledge, and provide a series of recommendations for future research.

INTRODUCTION

There is a well-established body of knowledge related to "nudging," a strategy that uses subtle stimuli to direct people's behavior within public health interventions, with the aim of changing behaviors to reduce the prevalence of non-communicable diseases. Recently, interventions to promote prevention and control of neglected tropical diseases have included nudging as a strategy for altering behavior. However, these interventions not been synthesized and present the opportunity for a scoping review.

INCLUSION CRITERIA

Eligible studies are those that include nudge strategies aimed at changing behavior to prevent and control neglected tropical diseases. All types of behavioral practices suitable for targeting neglected tropical diseases (e.g. handwashing behaviors) will be considered, not exclusively focusing on a specific type or group of neglected tropical diseases. The nudge strategy must be described in full, without restrictions to the study design. The context or population will be limited to low- and middle-income countries.

METHODS

A comprehensive search will be performed in the following databases: MEDLINE, PsycINFO, and Embase (Ovid), Web of Science Core Collection, CINAHL, ERIC, and EconLit (EBSCO), as well as registered trials and reviews in CENTRAL and PROSPERO to identify ongoing or unpublished studies. Titles will be screened by one reviewer, and non-eligible studies excluded. Two reviewers (SB and FVV) will screen abstracts independently. Eligible studies will be selected through a questionnaire that specifies the inclusion criteria. Papers selected for inclusion will be subject to data extraction using a tool designed by one review author and agreed upon by the other review authors. Data will be presented in a table and other conceptual styles.

Combining Web-Based Gamification and Physical Nudges With an App (MoveMore) to Promote Walking Breaks and Reduce Sedentary Behavior of Office Workers: Field Study

Background

Sedentary behavior (SB) and lack of physical activity (PA) have been associated with poorer health outcomes and are increasingly prevalent in individuals working in sedentary occupations such as office jobs. Gamification and nudges have attracted attention as promising strategies to promote changes in health behavior. However, most effectiveness studies thus far lacked active controls, and few studies have tested interventions combining these strategies.

Objective

This study investigates the effectiveness of combining a gamified digital app with physical nudges to increase PA and reduce SB in Dutch office workers.

Methods

Employees in the municipality of Rotterdam (N=298) from two office locations were randomized at the location level to either a 10-week intervention, combining a 5-week gamification phase encompassing a gamified digital app with social support features and a 5-week physical nudges phase, or to an active control (ie, basic digital app with self-monitoring and goal setting). The primary outcome was the daily step count, objectively measured via accelerometers. Secondary outcomes were self-reported PA and SB measured at baseline and at 5, 10, and 14 weeks. Mixed effects models were used to analyze the effects of the intervention on the outcome measures.

Results

A total of 78.5% (234/298) of participants completed the study and provided accelerometer data, whereas 36.9% (110/298) participants completed the self-report measures at 14 weeks. In the gamification phase, step count data were missing for 13.5% (473/3492) of observations in the control and 11.4% (445/3888) in the intervention condition; however, these percentages increased to 39.6% (1154/2910) and 59.6% (1932/3492) at follow-up, respectively. During the gamification phase, intervention participants increased their number of daily steps by 634 (95% CI 154.2-1113.8; P=.01) more than participants in the control group, after controlling for relevant factors. Improvements were not sustained during the physical nudges phase (P=.76) or follow-up (P=.88).

Conclusions

A digital intervention with gamification and social support features significantly increased the step count of office workers compared with an active control. Physical nudges in the workplace were insufficient to promote the maintenance of behavioral changes achieved in the gamification phase. Future research should explore the long-term effectiveness of similar gamified digital interventions.

Trial Registration

International Standard Randomized Controlled Trial Number (ISRCTN) 49129401; https://www.isrctn.com/ISRCTN14881571

Personalized hypertension management based on serial assessment and telemedicine (PHMA): a cluster randomize controlled trial protocol in Anhui, China

BACKGROUND

Despite tremendous investment worldwide, hypertension treatment and control rates remain low. The complexity and long-term dynamics of influencing factors make personalized management inevitable and challenging. This protocol describes Personalized Hypertension Management in Anhui, China (PHMA), a project that uses a package of innovative approaches in tailoring interventions to individual patient's dynamic complications and contexts.

METHODS/DESIGN

PHMA strives to reduce hypertension harms by eight "objective behaviors" (e.g., self-monitoring and reporting, healthy diet, physical exercise/activities). These objective behaviors are promoted through five intervention measures: support for self- monitoring, supervised machine communications, daily education or reminder messages, weekly blood pressure notification, and quarterly signed feedback. PHMA uses ten categories and over 300 variables in selecting and refining intervention procedures and content for individual patients. Efficacy of the intervention package is evaluated using a cluster randomized controlled trial design involving a total of 60 site communities and 3352 hypertension patients. Primary measure for the evaluation is systolic and diastolic blood pressure; while secondary evaluation measures include quality of life (EQ5D-5L), occurrence of hypertension-related complications (such as cerebral hemorrhage, coronary heart disease, myocardial or cerebral infarction), healthcare utilization and scores of objective behaviors.

DISCUSSION

PHMA uses novel, low cost and sustainable approaches to tailor interventions to the dynamic conditions and contexts of individual patients. Unlike contemporary approaches to hypertension management which are mainly population based, each participant patient in PHMA applies a unique intervention package and all messages, feedbacks and other materials sent out to individual patients are different from each other. PHMA is the first project that adopts comprehensive tailoring and if proved effective, it should have important implications for future research, practice and policy-making. Trial registration ISRCTN10999269. July 17, 2020; https://doi.org/10.1186/ISRCTN10999269 .

Contributions of Food Environments to Dietary Quality and Cardiovascular Disease Risk

PURPOSE OF REVIEW

To evaluate the multidimensional influence of food environments on food choice, dietary quality, and diet-related health and identify critical gaps necessary to develop effective population interventions that influence food choice.

RECENT FINDINGS

Multicomponent interventions that interact with multiple layers of the food environment show limited but consistent effects on dietary behaviors and may have wider and substantive population-level reach with greater incorporation of validated, holistic measurement tools. Opportunities to use smartphone technology to measure multiple components of the food environment will facilitate future interventions, particularly as food environments expand into online settings and interact with consumers in novel ways to shape food choice. While studies suggest that all dimensions of the food environment influence diet and health outcomes, robust and consistent measurements of food environments that integrate objective and subjective components are essential for developing stronger evidence needed to shift public policies.

Nutrition Interventions in Low-Income Rural and Urban Retail Environments: A Systematic Review

BACKGROUND

Nutrition interventions promoting healthy food choices aim to address health challenges of residents in low-income environments. Research about the effectiveness of nutrition interventions in low-income populations is limited, particularly for those in rural areas. Behavioral economics (BE) strategies demonstrate effectiveness for improving eating behaviors in some settings. However, the efficacy of BE interventions in retail food stores serving low-income populations residing in rural and urban geographies is nascent.

OBJECTIVE

This systematic literature review aims to identify and compare nutrition interventions implemented in rural and urban low-income retail food stores, including BE strategies when applied.

METHODS

This review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Reviewers searched five databases for peer-reviewed publications from October 2010 to October 2019. Included studies implemented a nutrition intervention in low-income retail food stores and provided a quantitative outcome evaluation with results separated by rural and urban geography. BE interventions were analyzed based on the MINDSPACE framework for behavior change.

RESULTS

Forty-six separate publications (n = 20 rural, n = 26 urban) in the United States, Canada, Europe, New Zealand, and Australia were included. Researchers independently rated publications as low risk of bias (n = 4), moderate (n = 18), or high risk of bias (n = 24) using the Quality Assessment Tool for Quantitative Studies. Studies (n = 18) demonstrated positive outcomes for customer purchases, store sales, or participant intake of targeted healthy foods. Overall, most effective interventions included point-of-purchase signage (n = 16) and product placement strategies (n = 4 urban). Rural studies included financial incentives combined with participant education (n = 2) and incorporated culturally appropriate messengers and/or symbols (n = 5) to improve healthy food purchases and intake.

CONCLUSIONS

Improved research quality and tailored evidence-based interventions, including BE strategies, are necessary in retail food environments to promote healthy eating behaviors in low-income populations.

Effect of front-of-package nutrition labeling on food purchases: a systematic review

OBJECTIVES

This study systematically reviewed evidence from interventions on the effect of front-of-package (FOP) nutrition labeling on food purchases.

STUDY DESIGN

The study design used in this study is a systematic review.

METHODS

Keyword search was performed in PubMed, Web of Science, Scopus, and Cochrane Library.

RESULTS

Fifteen studies (10 randomized controlled trials, four pre-post studies, and one case-control study) met the eligibility criteria and were included in the review. Five studies were conducted in a controlled setting through the establishment of an online virtual supermarket or physical laboratory food store solely for the intervention. In contrast, the remaining ten studies were conducted in a naturalistic setting where people commonly purchase foods (e.g., supermarket, grocery store, school/hospital cafeteria, or vending machine). FOP labels assessed included traffic lights, health star rating, daily intake guides, health warnings, and high sugar symbol labels. Compared with the control, FOP labels were effective for helping participants make healthier food purchase decisions in five of the 12 studies that assessed traffic lights labels, in one of the two studies that assessed health warning labels, and in one study that assessed high sugar symbol labels. Three assessed health star ratings and one assessed daily intake guide labels, but none revealed an effect on food purchases compared with the control.

CONCLUSIONS

Findings on the effectiveness of FOP nutrition labels in 'nudging' consumers toward healthier food purchases remain mixed and inconclusive. Future studies should examine other types of FOP labels beside the traffic lights labels and explore the different effects by consumer affordability, population subgroup, and shopping environment.

A nudge in the right direction: the role of food choice architecture in changing populations' diets

Populations' diets typically fall short of recommendations. The implication of this on ill health and quality of life is well established, as are the subsequent health care costs. An area of growing interest within public health nutrition is food choice architecture; how a food choice is framed and its influence on subsequent food selection. In particular, there is an appeal to manipulating the choice architecture in order to nudge individuals' food choice. This review outlines the current understanding of food choice architecture, theoretical background to nudging and the evidence on the effectiveness of nudge strategies, as well as their design and implementation. Interventions emphasising the role of nudge strategies have investigated changes to the accessibility, availability and presentation of food and the use of prompts. Empirical studies have been conducted in laboratories, online and in real-world food settings, and with different populations. Evidence on the effectiveness of nudge strategies in shifting food choice is encouraging. Underpinning mechanisms, not yet fully explicated, are proposed to relate to salience, social norms and the principle of least effort. Emerging evidence points to areas for development including the effectiveness of choice architecture interventions with different and diverse populations, and the combined effect of multiple nudges. This, alongside further examination of theoretical mechanisms and guidance to engage and inspire across the breadth of food provision, is critical. In this way, the potential of choice architecture to effect meaningful change in populations' diets will be realised.

Spontaneous Variety-Seeking Meal Choice in Business Canteens Impedes Sustainable Production

Sustainable meal choices in the out-of-home catering market are essential to attaining the Sustainable Development Goals. This study investigated consumers’ acceptance of different features that help service providers to work more sustainably. For this purpose, data of a choice experiment and a supporting online questionnaire were analyzed using latent class analysis (LCA) and the data of n = 373 employees. Examined attributes in the choice experiment were menu variety, menu type, ordering system, ingredients and price. LCA led to four consumer segments: variety seekers (27.6%), spontaneous decisionmakers—vegetarian (25.7%), spontaneous decisionmakers—meat (24.1%) and vegetarians/vegans (22.6%). Results showed that consumers in all four segments expected to have the choice between different menus in company canteens. Moreover, they preferred spontaneous choice to preordering. Both preferences hamper sustainable production and consumption in the catering sector.

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.

Nudging healthier food choices in a cafeteria setting: A sequential multi-intervention field study

Creating more health-fostering environments is high on the agenda of public and private actors. The behavioral approach to nudge people towards healthier food choices is gaining popularity despite limited understanding about where, and for whom, which specific nudges work. This study contributes by reporting on three different nudging interventions in the same setting and presents effects on different sub-populations. We find overall small effects that are heterogeneous, ranging from robustly more to even less healthy choices. We discuss the importance of transparency and reactance to health interventions and the potential interplay of interventions with habitual behavior among different sub-populations.

"AI's gonna have an impact on everything in society, so it has to have an impact on public health": a fundamental qualitative descriptive study of the implications of artificial intelligence for public health

Background

Our objective was to determine the impacts of artificial intelligence (AI) on public health practice.

Methods

We used a fundamental qualitative descriptive study design, enrolling 15 experts in public health and AI from June 2018 until July 2019 who worked in North America and Asia. We conducted in-depth semi-structured interviews, iteratively coded the resulting transcripts, and analyzed the results thematically.

Results

We developed 137 codes, from which nine themes emerged. The themes included opportunities such as leveraging big data and improving interventions; barriers to adoption such as confusion regarding AI’s applicability, limited capacity, and poor data quality; and risks such as propagation of bias, exacerbation of inequity, hype, and poor regulation.

Conclusions

Experts are cautiously optimistic about AI’s impacts on public health practice, particularly for improving disease surveillance. However, they perceived substantial barriers, such as a lack of available expertise, and risks, including inadequate regulation. Therefore, investment and research into AI for public health practice would likely be beneficial. However, increased access to high-quality data, research and education regarding the limitations of AI, and development of rigorous regulation are necessary to realize these benefits.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-020-10030-x.

And How Would That Make You Feel? How People Expect Nudges to Influence Their Sense of Autonomy

Objective

While nudges are increasingly utilized in public policy settings, their potential threat to autonomous choice is the topic of heated debate. Regardless of the actual effects of nudges on autonomy, the mere perception of nudges as autonomy threatening by the general public or policy makers could negatively influence nudge acceptability. The present online studies examined how people expect (different) nudges to affect their perception of autonomy.

Methods

In the first study (N = 455), participants were presented with a hypothetical choice that employed either a default nudge, direct persuasion, or no persuasion, to steer to the desired choice. The presented influence technique was explained before participants reported their expected autonomy, as well as their expected choice satisfaction. Study 2 (N = 601) involved a replication of Study 1 with an additional social norm nudge condition. In Study 3 (N = 750), the explanation of how choice had been influenced was omitted.

Results

While participants expected the default nudge to violate autonomy (Study 1), they had no such expectations for social norm nudges (Study 2). Omitting the explanation that most people are unaware of nudges influencing their choice, reduced the negative impact of nudges on expected autonomy (Study 3).

Conclusion

Effects of nudges on expectations of autonomy differ by type of nudge. Negative expectations are primarily driven by the explanation that decision makers are often unaware of nudges.