Search

Does clear and transparent communication of risks, benefits, and uncertainties increase or undermine public trust in scientific information that people use to guide their decision-making? We examined the impact of reframing messages written in traditional persuasive style to align instead with recent “evidence communication” principles, aiming to inform decision-making: communicating a balance of risks and benefits, disclosing uncertainties and evidence quality, and prebunking misperceptions. In two pre-registered experiments, UK participants read either a persuasive message or a balanced and informative message adhering to evidence communication recommendations about COVID-19 vaccines (Study 1) or nuclear power plants (Study 2). We find that balanced messages are either perceived as trustworthy as persuasive messages (Study 1), or more so (Study 2). However, we note a moderating role of prior beliefs such that balanced messages were consistently perceived as more trustworthy among those with negative or neutral prior beliefs about the message content. We furthermore note that participants who had read the persuasive message on nuclear power plants voiced significantly stronger support for nuclear power than those who had read the balanced message, despite rating the information as less trustworthy. There was no difference in vaccination intentions between groups reading the different vaccine messages.

Health warning labels (HWLs) show promise in reducing motivation towards energy-dense snack foods. Understanding the underlying mechanisms could optimise their effectiveness. In two experimental studies in general population samples (Study 1 n=90; Study 2 n=1382), we compared the effects of HWLs and irrelevant aversive labels (IALs) on implicit (approach) motivation towards unhealthy snacks, using an approach-avoidance task (Study 1), and a manikin task (Study 2). We also assessed explicit motivation towards unhealthy snacks using food selection tasks. We examined whether labelling effects on motivation arose from the creation of outcome-dependent associations between the food and its health consequences or from simple, non-specific aversive associations. Both label types reduced motivation towards snack foods but only when the label was physically present. HWLs and IALs showed similar effects on implicit motivation, although HWLs reduced explicit motivation more than IALs. Thus, aversive HWLs appear to act both through low level associative mechanisms affecting implicit motivation, and by additionally emphasizing explicit causal links to health outcomes thereby affecting explicitly motivated choice behaviours.

ObjectivesIndividuals who receive a negative lateral flow coronavirus test result may misunderstand it as meaning ‘no risk of infectiousness’, giving false reassurance. This experiment tested the impact of adding information to negative test result messages about residual risk and the need to continue protective behaviours.Design.4 (residual risk) × 2 (post-test result behaviours) between-subjects design.Setting.Online.Participants1200 adults from a representative UK sample recruited via Prolific (12–15 March 2021).InterventionsParticipants were randomly allocated to one of eight messages. Residual risk messages were: (1) ‘Your coronavirus test result is negative’ (control); (2) message 1 plus ‘It’s likely you were not infectious when the test was done’ (current NHS Test & Trace (T&T); (3) message 2 plus ‘But there is still a chance you may be infectious’ (elaborated NHS T&T); and (4) message 3 plus infographic depicting residual risk (elaborated NHS T&T+infographic). Each message contained either no additional information or information about the need to continue following guidelines and protective behaviours.Outcome measures(1) Proportion understanding residual risk of infectiousness and (2) likelihood of engaging in protective behaviours (scales 1–7).ResultsThe control message decreased understanding relative to the current NHS T&T message: 54% versus 71% (Adjusted Odds Ratio (AOR)=0.56 95% CI 0.34 to 0.95, p=0.030). Understanding increased with the elaborated NHS T&T (89%; AOR=3.25 95% CI 1.64 to 6.42, p=0.001) and elaborated NHS T&T+infographic (91%; AOR=5.16 95% CI 2.47 to 10.82, p2(1)=0.18, p=0.669), being high (M=6.4, SD=0.9) across the sample.ConclusionsA considerable proportion of participants misunderstood the residual risk following a negative test result. The addition of a single sentence (‘But there is still a chance you may be infectious’) to current NHS T&T wording increased understanding of residual risk.Trial registration numberOSF: https://osf.io/byfz3/

Background Effective interventions for reducing the consumption of products that harm population and planetary health often lack public support, impeding implementation. Communicating evidence of policies’ effectiveness can increase public support but there is uncertainty about the most effective ways of communicating this evidence. Some policies have multiple benefits such as both improving health and the environment. This study assesses whether communicating evidence of multiple versus single benefits of a policy increases its support. Method Participants (n = 4616) nationally representative of the British population were randomised to one of 24 groups in an online experiment with a 4 × 3 × 2 between-subjects factorial design. The messages that participants viewed differed according to the evidence they communicated (no message, effectiveness for changing behaviour, effectiveness for changing behaviour + one policy benefit, effectiveness for changing behaviour + three policy benefits), type of policy (taxation, availability) and the target behaviour (consumption of energy-dense food, alcohol, or meat). The primary outcome was policy support. Results In a full factorial ANOVA, there was a significant main effect of communicating evidence of effectiveness on policy support, which was similar across policies and behaviours. Communicating three benefits increased support relative to communicating one benefit (d = 0.15; p = 0.01). Communicating one benefit increased support compared to providing evidence for changing behaviour alone (d = 0.13; p = 0.004) or no message (d = 0.11 p = 0.022). Conclusion Communicating evidence of a policy's benefits increases support for policy action across different behaviours and policies. Presenting multiple benefits of policies enhances public support.

Theresa Marteau and colleagues argue for rapid, radical changes to the infrastructure and pricing systems that currently support unhealthy unsustainable behaviour

Background Observational evidence suggests that cigarette pack size – the number of cigarettes in a single pack – is associated with consumption but experimental evidence of a causal relationship is lacking. The tobacco industry is introducing increasingly large packs, in the absence of maximum cigarette pack size regulation. In Australia, the minimum pack size is 20 but packs of up to 50 cigarettes are available. We aimed to estimate the impact on smoking of reducing cigarette pack sizes from ≥25 to 20 cigarettes per pack. Method A two-stage adaptive parallel group RCT in which Australian smokers who usually purchase packs containing ≥25 cigarettes were randomised to use only packs containing either 20 (intervention) or their usual packs (control) for four weeks. The primary outcome, the average number of cigarettes smoked per day, was measured through collecting all finished cigarette packs, labelled with the number of cigarettes participants smoked. An interim sample size re-estimation was used to evaluate the possibility of detecting a meaningful difference in the primary outcome. Results The interim analysis, conducted when 124 participants had been randomised, suggested 1122 additional participants needed to be randomised for sufficient power to detect a meaningful effect. This exceeded pre-specified criteria for feasible recruitment, and data collection was terminated accordingly. Analysis of complete data (n = 79) indicated that the mean cigarettes smoked per day was 15.9 (SD = 8.5) in the intervention arm and 16.8 (SD = 6.7) among controls (difference − 0.9: 95%CI = − 4.3, 2.6). Conclusion It remains unclear whether reducing cigarette pack sizes from ≥25 to 20 cigarettes reduces cigarette consumption. Importantly, the results of this study provide no evidence that capping cigarette pack sizes would be ineffective at reducing smoking. The limitations identified in this study can inform a more efficient RCT, which is urgently required to address the dearth of experimental evidence on the impact of large cigarette pack sizes on smoking. Trial registration 10.1186/ISRCTN34202533

Conservation is predominantly an exercise in trying to change human behaviour – whether that of consumers whose choices drive unsustainable resource use, of land managers clearing natural habitats, or of policymakers failing to deliver on environmental commitments. Yet conservation research and practice have made only limited use of recent advances in behavioural science, including more novel behaviour change interventions. Instead conservationists mostly still rely on traditional behaviour change interventions – education, regulation and material incentivisation – largely without applying recent insights from behavioural science about how to improve such approaches. This paper explores how behavioural science could be more widely and powerfully applied in biodiversity conservation. We consider the diverse cast of actors involved in conservation problems and the resulting breadth of behaviour change that conservationists might want to achieve. Drawing on health research, we present a catalogue of types of interventions for changing behaviour, considering both novel, standalone interventions and the enhancement of more traditional conservation interventions. We outline a framework for setting priorities amongst interventions based on their likely impact, using ideas developed for climate change mitigation. We caution that, despite its promise, behavioural science is not a silver bullet for conservation. The effects of interventions aimed at changing behaviour can be modest, temporary, and context-dependent in ways that are as-yet poorly understood. We therefore close with a call for interventions to be tested and the findings widely disseminated to enable researchers and practitioners to build a much-needed evidence base on the effectiveness and limitations of these tools.

BACKGROUND: Placing food further away from people decreases likelihood of consumption ("Proximity Effect"). However, it is unclear how proximity affects consumption when both healthier and less healthy foods are available and cognitive resource for self-control is limited. AIMS: To test the hypothesis that when both healthier (raisins) and less healthy (chocolate M&Ms) foods are available, placing less healthy food far, rather than near, increases the likelihood that healthier food is consumed. METHODS: General population participants (N = 248) were all put under cognitive load and randomised to one of four groups: 1. Raisins near (20 cm), M&Ms far (70 cm); 2. Both foods near; 3. M&Ms near, raisins far; 4. Both far. PRIMARY OUTCOME: proportions of participants consuming raisins and M&Ms, respectively. RESULTS: The results did not support the primary hypothesis: when healthier and less healthy foods were both available, placing M&Ms far, rather than near, did not increase likelihood of consuming raisins (OR = 1.54, p = .432). Regardless of the M&Ms proximity, likelihood of consuming raisins was unaffected by the raisins' proximity (62.9%(near) vs. 56.5%(far) OR = 0.61, p = .211). Likelihood of consuming M&Ms non-significantly decreased when they were far and raisins were near, and when both foods were far (OR = 2.83, p = .057). Likelihood of consuming M&Ms was affected by M&Ms proximity, being higher when near (68.3%) than far (55.6%), OR = 0.39, p = .015. Indices of cognitive load impact (higher vs lower) were unrelated to consumption of either food. CONCLUSIONS: Likelihood of consuming a healthier food was unaffected by its proximity and that of a less healthy food. By contrast, likelihood of consuming a less healthy food was influenced by its proximity and possibly by that of a healthier food. These effects need replication in studies designed to detect smaller effect sizes. TRIAL REGISTRATION: This study was registered online with ISRCTN (ISRCTN11740813).

Background Straight-sided glasses can slow the rate of lager consumption in a laboratory setting compared with curved glasses. Slower drinking rates may lower overall alcohol consumption. Glass shape is therefore a potential target for intervention. The aim of this randomised crossover trial was to estimate the impact of serving draught beer and cider in straight-sided glasses, compared with usual, predominantly curved glasses, on alcohol sales for on-site consumption in bars. Methods Twenty-four bars in England completed two intervention periods (A) and two control periods (B) in a randomised order: 1) BABA; 2) BAAB; 3) ABBA; or 4) ABAB. Each period lasted two weeks and involved serving draught beer and cider in either straight-sided glasses (A) or the venue's usual glasses (≥75% curved; B). The primary outcome was the mean volume (in litres) of draught beer and cider sold weekly, compared between A and B periods using a paired-samples t-test on aggregate data. A regression model adjusted for season, order, special events, and busyness. Findings Mean weekly volume sales of draught beer and cider was 690·9 L (SD 491·3 L) across A periods and 732·5 L (SD 501·0 L) across B periods. The adjusted mean difference (A minus B) was 8·9 L per week (95% CI -45·5 to 63·3; p = 0·737). Interpretation This study provides no clear evidence that using straight-sided glasses, compared with usual, predominantly curved glasses, reduces the volume of draught beer and cider sold for on-site consumption in bars., Graphical abstract Image 1, HIGHLIGHTS • Straight-sided glasses do not reduce beer sales in bars versus usual glasses. • Usual beer glasses are predominantly curved, but there are many different types. • Other interventions may warrant attention, such as reducing serving sizes.

Background: Increasing the availability of lower energy foods increases their selection. The current studies examine the extent to which this effect could be mediated by social norms – assessed by perceived popularity of foods – which may be implied by their relative availability. Methods: Study 1 (Online): 2340 UK adults estimated the perceived popularity of lower energy products. For each of eight trials, participants were randomised to one of six groups (between-subjects 3x2) to see photos of cafeteria shelves varying in the availability of lower energy options (1/4 lower energy; 1/2 lower energy; 3/4 lower energy) and fullness of shelves (fuller; emptier).Study 2 (Laboratory): 139 English adults were asked to select a snack. Participants were randomised to select from trays varying in the availability of the lower energy option (1/3 lower energy; 2/3 lower energy) and fullness of tray (fuller; emptier). Results: Study 1: Evidence for an interaction was found, such that when shelves were full, a higher proportion of lower energy options led to greater perceived popularity of lower energy products (1/4 lower energy: 40.9% (95%CIs: 40.1,41.8); 3/4 lower energy: 47.2% (46.3,48.0)), whereas when shelves were emptier, a higher proportion of lower energy options led to lower perceived popularity (1/4 lower energy: 48.4% (47.5,49.2); 3/4 lower energy: 39.2% (38.3,40.0)).Study 2: When the tray was fuller, participants were more likely – albeit non-significantly (main effects: p=0.05; interactions: p=0.07) – to select a lower energy snack when 2/3 of the available snacks were lower energy (35.7% (18.5,52.9)) than when 1/3 were lower energy (15.4% (4.2,26.5)). For emptier trays, lower energy selections decreased as the relative availability of lower energy snacks increased (1/3 lower energy snacks: 36.0% (17.9,54.1); 2/3 lower energy snacks: 27.8% (13.9,41.7)). Conclusions:These studies provide novel evidence that social norms may mediate the impact of availability on food selection. In addition, they suggest that the effect of availability may vary in different contexts, moderated by display layout through its impact on perceived product popularity. Trial registration. ISRCTN: ISRCTN10512908; 31/01/2020

Theresa Marteau and colleagues argue that behavioural and social causes of poor health must be tackled in parallel to reduce inequalities

The success of mass COVID-19 vaccination campaigns rests on widespread uptake. However, although vaccinations provide good protection, they do not offer full immunity and while they likely reduce transmission of the virus to others, the extent of this remains uncertain. This produces a dilemma for communicators who wish to be transparent about benefits and harms and encourage continued caution in vaccinated individuals but not undermine confidence in an important public health measure. In two large pre-registered experimental studies on quota-sampled UK public participants we investigate the effects of providing transparent communication—including uncertainty—about vaccination effectiveness on decision-making. In Study 1 ( n = 2,097) we report that detailed information about COVID-19 vaccines, including results of clinical trials, does not have a significant impact on beliefs about the efficacy of such vaccines, concerns over side effects, or intentions to receive a vaccine. Study 2 ( n = 2,217) addressed concerns that highlighting the need to maintain protective behaviours (e.g. social distancing) post-vaccination may lower perceptions of vaccine efficacy and willingness to receive a vaccine. We do not find evidence of this: transparent messages did not significantly reduce perceptions of vaccine efficacy, and in some cases increased perceptions of efficacy. We again report no main effect of messages on intentions to receive a vaccine. The results of both studies suggest that transparently informing people of the limitations of vaccinations does not reduce intentions to be vaccinated but neither does it increase intentions to engage in protective behaviours post-vaccination.

BackgroundExcessive consumption of energy-dense food increases the risk of obesity, which in turn increases the risk of non-communicable diseases, including heart disease, type 2 diabetes and most non-smoking-related cancers. Health warning labels (HWLs) that communicate the adverse health consequences of excess energy consumption could reduce intake of energy-dense foods. The aim of the current study was to estimate the impact on selection of energy-dense snacks of (a) image-and-text HWLs (b) text-only HWLs and (c) calorie information. Methods A between-subjects, 3 (HWL: image-and-text, text-only, no label) x 2 (calorie information: present, absent), factorial experimental design. Participants (N=4,134) were randomised to view a selection of energy-dense and non-energy-dense snacks with one of five label types or no label. The primary outcome was the proportion of participants selecting an energy-dense snack in a hypothetical vending machine task.ResultsThe proportion of participants selecting an energy-dense snack was reduced in all label groups, relative to the no label group (image-and-text HWL: 37%; image-and-text HWL with calories: 38%; text-only HWL: 48%; text-only HWL with calories: 44%; calories only: 54%; no label: 59%). Participants were least likely to select an energy-dense snack in the image-and-text HWL group and most likely in the no label group (OR = 0.46, 95%CI = 0.40, 0.54, p < 0.001).Conclusions Health warning labels – particularly those including an image and text - have the potential to reduce selection of energy-dense snacks in an online setting. Their impact on selection and consumption in real-world settings awaits testing.Trial registration: The study protocol (https://osf.io/6n7h9, registered: April 1st 2019) and data analysis plan (https://osf.io/zvrs5) were pre-registered on the Open Science Framework. KeywordsHealth warning labels, pictorial labels, graphic warnings, snacks, food, choice architecture, energy-dense

Avoid unwarranted certainty, neat narratives and partisan presentation; strive to inform, not persuade. Avoid unwarranted certainty, neat narratives and partisan presentation; strive to inform, not persuade.

The health of populations across the planet is in a perilous state during the COVID-19 pandemic, with more than 550 000 deaths worldwide as of July 10, 2020.1 The disease burden is falling mainly on the most disadvantaged groups worldwide and there are major impacts on health systems across high, middle, and low-income countries. In parallel with these direct health impacts, the economic effects of lockdowns are leading to an unprecedented global recession which will have ramifications well into the future. But while the focus is, rightly, on responding to the immediate threat of the pandemic, it is important to remember that over 40 million people die each year from non-communicable diseases (NCDs), more than 70% of all global deaths.

Introduction There is an absence of evidence regarding the impact of treating tobacco smoking and vaping equivalently in workplace policies. We aimed to describe and compare smoking and vaping policies in acute nonspecialist NHS Trusts (n = 131) and Higher Education Institutions (HEIs) (n = 131) in England. Methods We conducted a census of smoking and vaping policies through organizational websites searches and direct requests for information. We recorded whether and where smoking and vaping were permitted. Results Smoking was prohibited indoors in all organizations. No NHS Trust permitted smoking freely outdoors, in contrast with 60% of HEIs. In 27% of NHS Trusts and 33% of HEIs smoking was permitted in designated areas, while in 73% of NHS Trusts and 8% of HEIs smoking was prohibited anywhere on site. Vaping was prohibited indoors in all NHS Trusts and all but one HEI, but permitted freely outdoors in 18% of NHS Trusts and 75% of HEIs. Vaping was permitted in designated outdoor spaces in 23% of NHS Trusts: 21% had areas shared with smokers; 2% had separate vaping areas. Vaping was permitted in designated outdoor areas in 18% of HEIs, all of which were shared with smokers. Vaping was prohibited anywhere on site in 54% of NHS Trusts and 6% of HEIs. Conclusions Policies vary considerably in whether vaping and smoking are treated equivalently. Smoking policies in most HEIs should be reviewed to include more effective tobacco control approaches. Evidence is needed on the impact of imposing shared or separate spaces on vapers and smokers. Implications This report provides a comprehensive review of smoking and vaping policies in two types of organization across England. It highlights key discrepancies between current public health recommendations for vaping and existing workplace policies, which often lead to smokers and vapers sharing spaces. The report identifies the need for evidence on the impact of imposing shared spaces on smokers and vapers to inform workplace policies that maximize public health benefit.

Altering the order in which meals are presented at cafeteria counters has been proposed as a way of lowering meat consumption, but remains largely untested. To address this, we undertook two experimental studies involving 105,143 meal selections in the cafeterias of a British university. Placing vegetarian options first on the counter consistently increased their sales when choices were widely separated (>1.5 m; vegetarian sales as a percentage of total meal sales increased by 4.6 and 6.2 percentage points) but there was no evidence of an effect when the options were close together (

Risk compensation - increasing a risky behaviour following engagement in a protective behaviour - has been used to argue against public health measures, including the wearing of face coverings for reducing transmission of SARS-CoV-2 Available evidence does not support concern that wearing face coverings adversely affects hand hygiene Evidence from other areas also indicates that risk compensation is not is not discernible at a population level i.e. when assessing the average change in an outcome following an intervention l The concept of risk compensation – not risk compensation per se - appears the greater threat to public health from delaying potentially effective interventions.

Background Increasing the availability of healthier food increases its selection and consumption. However, there is an absence of evidence related to alcohol. This study aimed to estimate the impact of increasing the absolute and relative availability of non-alcoholic compared to alcoholic drinks on selection. We also assessed whether effects were modified by cognitive resource. Methods UK adult weekly alcohol consumers (n = 808) were recruited to an online experiment with a hypothetical drink selection task. Participants were randomly assigned to one of eight conditions, in a 4 (availability) × 2 (cognitive resource) factorial design. The four availability conditions were: i. Reference 1 (two non-alcoholic, two alcoholic drinks); ii. Reference 2 (four non-alcoholic, four alcoholic drinks); iii. Increased non-alcoholic drinks (six non-alcoholic, two alcoholic drinks); iv. Increased alcoholic drinks (two non-alcoholic, six alcoholic drinks). The two cognitive resource conditions were: a. Low (high time pressure); b. High (low time pressure). Logistic regression was used to assess selection of a non-alcoholic drink. Results 49% of participants selected a non-alcoholic drink in the Increased non-alcoholic drinks condition, compared to 36% in Reference 1, 39% in Reference 2, and 26% in the Increased alcoholic drinks condition. Non-alcoholic drink selection was similar between Reference 1 and 2 when the total number of drinks increased (absolute availability) but the proportion of non-alcoholic compared to alcoholic drinks (relative availability) was unchanged (OR = 1.15, 95% CI 0.77, 1.73). In contrast, the odds of selecting a non-alcoholic drink were 71% higher when both absolute and relative availability of non-alcoholic compared to alcoholic drinks was increased from Reference 1 to the Increased non-alcoholic drinks condition (OR: 1.71, 95% CI 1.15, 2.54), and 48% higher when increased from Reference 2 to the Increased non-alcoholic drinks condition (OR: 1.48, 95% CI 0.99, 2.19). There was no evidence of an effect of cognitive resource. Conclusions Greater availability of non-alcoholic drinks, compared to alcoholic drinks, increased their online selection, an effect that may be larger when changing their relative availability, i.e., increasing the proportion of non-alcoholic drinks. Naturalistic studies are needed to determine the impact of availability interventions on reducing alcohol purchasing and consumption.

Aims:- \ud \ud Evidence from tobacco research suggests that health warning labels (HWLs) depicting the adverse consequences of consumption change smoking behaviours, with image-and-text (also known as ‘pictorial’ or ‘graphic’) HWLs most effective. There is an absence of evidence concerning the potential impact of HWLs placed on alcohol products on selection of those products. This study aimed to obtain a preliminary assessment of the possible impact of (i) image-and-text, (ii) text-only, and (iii) image-only HWLs on selection of alcoholic versus non-alcoholic drinks.\ud Design:- \ud \ud A between-subjects randomised experiment with a 2 (image: present versus absent) × 2 (text: present versus absent) factorial design.\ud Setting:- \ud \ud The study was conducted on the online survey platform Qualtrics.\ud Participants:- \ud \ud Participants (n = 6024) were adults over the age of 18 who consumed beer or wine regularly (i.e. at least once a week), recruited through a market research agency.\ud Interventions:- \ud \ud Participants were randomised to one of four groups varying in the HWL displayed on the packaging of alcoholic drinks: (i) image-and-text HWL; (ii) text-only HWL; (iii) image-only HWL; and (iv) no HWL. HWLs depicted bowel cancer, breast cancer and liver cancer, which were each displayed twice across six alcoholic drinks. Each group viewed six alcoholic and six non-alcoholic drinks and selected one drink that they would like to consume.\ud Measurements:- \ud \ud The primary outcome was the proportion of participants selecting an alcoholic versus a non-alcoholic drink.\ud Findings:- \ud \ud Alcoholic drink selection was lower for all HWL types compared with no HWL (image-and-text: 56%; image-only: 49%; text-only: 61%; no HWL: 77%), with selection lowest for HWLs that included an image. Image-and-text HWLs reduced the odds of selecting an alcoholic drink compared with text-only HWLs (OR = 0.80, 95% CI = 0.69, 0.92), but increased the odds of selecting an alcoholic drink compared with image-only HWLs (OR = 1.34, 95% CI = 1.16, 1.55).\ud Conclusions:- \ud \ud Health warning labels communicating the increased risk of cancers associated with alcohol consumption reduced selection of alcoholic versus non-alcoholic drinks in a hypothetical choice task in an online setting; labels displaying images had the largest effect. Their impact in laboratory and real-world field settings using physical products awaits investigation.

BackgroundReducing alcohol consumption across populations would prevent many non-communicable diseases. Large packages increase food and non-alcoholic drink consumption and large glasses increase wine consumption. Smaller bottles may reduce alcohol consumption but their impact is uncertain. This study aims to (i) explore the feasibility and acceptability of conducting a large-scale randomised study to assess the impact of bottle size on in-home wine consumption and (ii) estimate the effect size and variance of the intervention on consumption to inform the design of future studies.MethodsCross-over randomised study in which 16 households in Cambridge, England, consuming at least two 750-ml bottles of wine each week, received a pre-set volume of wine biweekly for 4 weeks, in 750-ml and 375-ml bottles, in random order. Consumption was assessed by recording the number of empty and partially full bottles at the end of each biweekly period. At the end of the study, household representatives were interviewed about their experiences of participating in the study.ResultsThe study procedures proved feasible. Comparable to similar trials, 14% of identified eligible households (18/125) consented to participate in the study. Attrition between consent and study completion was 11% (2/18) and 0% between study periods and 13% of households (2/16) correctly identified the study aim. The study procedures were considered acceptable. After adjusting for guest and out-of-home consumption, the difference in consumption between the 750-ml (3385.2 ml; SD = 1698.5) and 375-ml bottles (3376.7 ml; SD = 1719.0) was 8.4 ml (SD = 1235.4; 95%CI − 596.9, 613.8). Results suggest a possible order effect, with households receiving the 375-ml bottles first consuming more wine out of the 750-ml bottles and vice versa. This might also reflect an increase in consumption with study duration. Households receiving the 375-ml bottles first (6315.9 ml; SD = 3293.5) also drank less wine overall than those receiving the 750-ml bottles first (7335.4 ml; SD = 3735.4).DiscussionThe findings support the feasibility and acceptability of running a large-scale randomised study to assess the impact of bottle size on in-home wine consumption. Due to the heterogeneous patterning of results, a future study will be powered using the variance observed in the current study to detect a meaningful reduction of 250 ml of wine when consumed from smaller compared with larger bottles.Trial registrationOpen Science Framework (OSF):rmk43; May 23, 2017.

Sugar-sweetened beverages (SSBs) are one of the largest added sugar sources to diets in the UK and USA. Health warning labels reduce hypothetical selection of SSBs in online studies but uncertainty surrounds their impact on selection of drinks for consumption. Calorie information labels are also promising but their impact on SSB selection is unclear. This laboratory study assessed the impact on SSB selection of ‘on-pack’ labels placed directly on physical products: i.a pictorial health warning label depicting an adverse health consequence of excess sugar consumption; and ii.calorie information labels. Potential moderation of any effects by socio-economic position (SEP) was also examined. Participants - 401 adults, resident in England, approximately half of whom were of lower SEP and half of higher SEP, were asked to select a drink from a range of two non-SSBs and four SSBs (subsequent to completing a separate study assessing the effects of food availability on snack selection). The drinks included ‘on-pack’ labels according to randomisation: Group 1: pictorial health warning label on SSBs; Group 2: calorie information label on all drinks; Group 3: no additional label. The primary outcome was the proportion of participants selecting an SSB. Compared to not having additional labels (39%), neither the pictorial health warning label (40%) nor calorie information labels (43%) affected the proportion of participants selecting an SSB. Lower SEP participants (45%) were more likely to select an SSB compared to those of higher SEP (35%), but SEP did not moderate the impact of labels on drink selection. In conclusion, pictorial health warning labels may be less effective in reducing SSB selection in lab-based compared with online settings, or depending on label design and placement. Findings suggest that effects might be absent when choosing from real products with actual ‘on-pack’ labels, positioned in a ‘realistic’ manner. Field studies are needed to further assess the impact of ‘on-pack’ SSB warning labels in real-world settings to rule out the possible contribution of study design factors.

Background Overconsumption of food, alcohol, and tobacco products increases the risk of non‐communicable diseases. Interventions to change characteristics of physical micro‐environments where people may select or consume these products ‐ including shops, restaurants, workplaces, and schools – are of considerable public health policy and research interest. This review addresses two types of intervention within such environments: altering the availability (the range and/or amount of options) of these products, or their proximity (the distance at which they are positioned) to potential consumers. Objectives 1. To assess the impact on selection and consumption of altering the availability or proximity of (a) food (including non‐alcoholic beverages), (b) alcohol, and (c) tobacco products. 2. To assess the extent to which the impact of these interventions is modified by characteristics of: i. studies, ii. interventions, and iii. participants. Search methods We searched CENTRAL, MEDLINE, Embase, PsycINFO, and seven other published or grey literature databases, as well as trial registries and key websites, up to 23 July 2018, followed by citation searches. Selection criteria We included randomised controlled trials with between‐participants (parallel group) or within‐participants (cross‐over) designs. Eligible studies compared effects of exposure to at least two different levels of availability of a product or its proximity, and included a measure of selection or consumption of the manipulated product. Data collection and analysis We used a novel semi‐automated screening workflow and applied standard Cochrane methods to select eligible studies, collect data, and assess risk of bias. In separate analyses for availability interventions and proximity interventions, we combined results using random‐effects meta‐analysis and meta‐regression models to estimate summary effect sizes (as standardised mean differences (SMDs)) and to investigate associations between summary effect sizes and selected study, intervention, or participant characteristics. We rated the certainty of evidence for each outcome using GRADE. Main results We included 24 studies, with the majority (20/24) giving concerns about risk of bias. All of the included studies investigated food products; none investigated alcohol or tobacco. The majority were conducted in laboratory settings (14/24), with adult participants (17/24), and used between‐participants designs (19/24). All studies were conducted in high‐income countries, predominantly in the USA (14/24). Six studies investigated availability interventions, of which two changed the absolute number of different options available, and four altered the relative proportion of less‐healthy (to healthier) options. Most studies (4/6) manipulated snack foods or drinks. For selection outcomes, meta‐analysis of three comparisons from three studies (n = 154) found that exposure to fewer options resulted in a large reduction in selection of the targeted food(s): SMD −1.13 (95% confidence interval (CI) −1.90 to −0.37) (low certainty evidence). For consumption outcomes, meta‐analysis of three comparisons from two studies (n = 150) found that exposure to fewer options resulted in a moderate reduction in consumption of those foods, but with considerable uncertainty: SMD −0.55 (95% CI −1.27 to 0.18) (low certainty evidence). Eighteen studies investigated proximity interventions. Most (14/18) changed the distance at which a snack food or drink was placed from the participants, whilst four studies changed the order of meal components encountered along a line. For selection outcomes, only one study with one comparison (n = 41) was identified, which found that food placed farther away resulted in a moderate reduction in its selection: SMD −0.65 (95% CI −1.29 to −0.01) (very low certainty evidence). For consumption outcomes, meta‐analysis of 15 comparisons from 12 studies (n = 1098) found that exposure to food placed farther away resulted in a moderate reduction in its consumption: SMD −0.60 (95% CI −0.84 to −0.36) (low certainty evidence). Meta‐regression analyses indicated that this effect was greater: the farther away the product was placed; when only the targeted product(s) was available; when participants were of low deprivation status; and when the study was at high risk of bias. Authors' conclusions The current evidence suggests that changing the number of available food options or altering the positioning of foods could contribute to meaningful changes in behaviour, justifying policy actions to promote such changes within food environments. However, the certainty of this evidence as assessed by GRADE is low or very low. To enable more certain and generalisable conclusions about these potentially important effects, further research is warranted in real‐world settings, intervening across a wider range of foods ‐ as well as alcohol and tobacco products ‐ and over sustained time periods., Plain language summary Altering the availability or proximity of food, alcohol, and tobacco products to change their selection and consumption Unhealthy patterns of consumption of food, alcohol, and tobacco products are important causes of ill health. Changing the availability (the range or amount of options, or both) of these products or their proximity (the distance at which they are positioned) to potential consumers could help people make healthier choices. What is the aim of this review? This review investigated whether altering the availability or proximity of food (including non‐alcoholic beverages), alcohol, and tobacco products changed people's selection (such as purchasing) or consumption of those products. We searched for all available evidence from randomised controlled trials (a type of study in which participants are assigned to one of two or more treatment groups using a random method) to answer this question, and found 24 studies, all of which were conducted in high‐income countries. What are the main results of the review? Six studies involved availability interventions, of which four changed the relative proportion of less‐healthy to healthier options, and two changed the absolute number of different options available. In statistical analyses that combined results from multiple studies, it was found that reducing the number of available options for a particular range or category of food(s) reduced selection of those food products (from analysing 154 participants) and possibly reduced consumption of those products (from 150 participants). However, the certainty of the evidence for these effects was low. Eighteen studies involved proximity interventions. Most (14/18) changed the distance at which a snack food or drink was placed from the participants, whilst four studies changed the order of meal components encountered along a line. One study found that this reduced selection of food (from analysing 41 participants), whilst in a statistical analysis combining results from multiple studies, it was found that placing food farther away reduced consumption of those food products (from analysing 1098 participants). However, the certainty of the evidence for these effects was very low and low, respectively. Key messages Mindful of its limitations, the current evidence suggests that changing the number of available food options or changing where foods are positioned could contribute to meaningful changes in behaviour, justifying policy actions to promote such changes to food environments. However, more high‐quality studies in real‐world settings are needed to make this finding more certain. How up‐to‐date is this review? The evidence is current to 23 July 2018.

Background Calorie labelling may help to reduce energy consumption, but few well-controlled experimental studies have been conducted in real world settings. In a previous randomised controlled pilot trial we did not observe an effect of calorie labelling on energy purchased in worksite cafeterias. In the present study we sought to enhance the effect by making the labels more prominent, and to address the operational challenges reported previously by worksites. Methods Three worksite cafeterias were randomised in a stepped wedge design to start the intervention at one of three fortnightly periods between March and July 2018. The intervention comprised introducing prominent calorie labelling for all cafeteria products for which calorie information was available (on average 87% of products offered across the three sites were labelled). Calorie content was displayed in bold capitalised Verdana typeface with a minimum font size of 14 e.g. 120 CALORIES. Feasibility and acceptability were assessed using post-intervention surveys with cafeteria patrons and semi-structured interviews with managers. Effectiveness was assessed using total daily energy (kcal) purchased from intervention items across the three sites, analysed using semi-parametric GAMLSS models. Results Recruitment and retention of worksite cafeterias proved feasible: all three randomised sites successfully completed the study. Post-intervention feedback suggested high levels of intervention acceptability: 87% of responding patrons wanted calorie labelling to remain in place. No effect of the intervention on daily energy purchased was observed: −0.6% (95%CI -2.5 to 1.2, p = .487). By-site analyses showed similar null effects at each of the three sites, all ps > .110. Conclusions There was no evidence that prominent calorie labelling changed daily energy purchased across three English-based worksite cafeterias. The intervention was feasible to implement and acceptable to patrons and managers.

Objective Previous research suggests that wine glass size affects sales of wine in bars, with more wine purchased when served in larger glasses. The current four studies, conducted in one restaurant (Studies 1 and 2) and two bars (Studies 3 and 4) in Cambridge, England, aim to establish the reproducibility of this effect of glass size on sales. A multiple treatment reversal design was used, involving wine being served in sequential fortnightly periods in different sized glasses of the same design (290 ml, 350 ml, and 450 ml). The primary outcome was daily wine volume (ml) sold. Results Restaurant: Daily wine volume sold was 13% (95% CI 2%, 24%) higher when served with 350 ml vs. 290 ml glasses in Study 1. A similar direction of effect was seen in Study 2 (6%; 95% CI − 1%, 15%). Bars: Daily wine volume sold was 21% (95% CI 9%, 35%) higher when served with 450 ml vs. 350 ml glasses in Study 3. This effect was not observed in Study 4 (− 7%, 95% CI − 16%, 3%). Meaningful differences were not demonstrated with any other glass comparison. These results partially replicate previous studies showing that larger glasses increase wine sales. Considerable uncertainty remains about the magnitude of any effect and the contexts in which it might occur. Trial registration Study 1: ISRCTN17958895 (21/07/2017), Study 2: ISRCTN17097810 (29/03/2018), Study 3 and 4: ISRCTN39401124 (10/05/2018)

In 2018, the UK Government’s Secretary of State for Health and Social Care articulated an ambition to increase healthy life expectancy by five years by 2035 for England, while also reducing the gap in this between the rich and the poor1. While we doubt that England – or indeed any high-income country – could achieve this ambition, we describe a set of policies with the potential to make a significant contribution.

ObjectivesAlcohol consumption is the fifth leading cause of morbidity and mortality globally. The development and promotion of lower strength alcohol products may help reduce alcohol consumption and associated harms. This study assessed what a sample of UK weekly drinkers perceived to be the target groups and occasions for drinking wines and beers labelled with different verbal and numerical descriptors of lower alcohol strength.Design and participants3390 adults (1697 wine and 1693 beer drinkers) were sampled from a nationally representative UK panel, and participated in a between-subjects experiment in which participants were randomised to 1 of 18 groups with one of three levels of verbal descriptor (Lowvs.Super Lowvs.No verbal descriptor) and six levels of %ABV (five levels varying for wine and beer, and no level given).MeasuresThe study gauged participants’ perceptions of the type of person that would find the randomised beverage appealing and the type of occasion on which the beverage is likely to be drunk at.ResultsA principal component analysis showed that participants perceived pregnant women, sportspeople and those aged 6–13 years old were the target groups for products labelled with 0%ABV or the verbal descriptorsLoworSuper Low, whereas men, women, and those aged above 18 were perceived as the target groups for products labelled with higher %ABV. Participants also rated the products labelled with 0%ABV or the verbal descriptorsLoworSuper Lowas targeting consumption on weekday lunches, whereas products labelled with higher %ABV were rated as targeting dinner/evening occasions, including parties, holidays and celebrations.ConclusionsLower strength products were seen as targeting non-traditional consumers (pregnant women) and occasions (weekday lunchtimes), suggesting these products may be perceived as extensions to regular strength alcoholic drinks rather than as substitutes for them.

Altering the availability of products (e.g. food, alcohol or tobacco products) is one potential intervention to change behaviours to help reduce preventable premature deaths worldwide. However, research on these interventions lacks consistent conceptualisation, hindering clear reporting and cumulative synthesis. This paper proposes a conceptual framework – categorising intervention types and summarising constituent components – with which interventions can be reliably described and evidence synthesised. Three principal distinctions are proposed: interventions altering: (i) Absolute Availability (changing the overall number of options, while keeping the proportions comprised by any subsets of options constant); (ii) Relative Availability (changing the proportion comprised by a subset of options, yet keeping the overall number of options constant); (iii) Absolute and Relative Availability (changing both the overall number of options and the proportions comprised by subsets of options). These are subdivided into those targeting (a) a product or (b) a category of products. Mechanisms that might underlie each of these intervention types are discussed, and implications for future research highlighted. The proposed framework aims to facilitate study of a set of interventions that could contribute significantly to healthier behaviour across populations.

Uncertainties remain about the overall effect of sit-stand desks for reducing prolonged sitting among office-based workers. This study assessed the feasibility of a randomised controlled trial of the impact of workplace sit-stand desks on overall energy expenditure, sitting time and cardio-metabolic outcomes. It involved four phases: Phase I: online survey; Phase II: workspace auditing; Phase III: randomised intervention (provision of sit-stand desks at work for 3 months); Phase IV: qualitative component. Participants were offıce-based employees of two companies in Cambridge, England. Among Phase I participants interested in the trial, 100 were randomised to Phase II. Of those with workspaces suitable for sit-stand desks, 20 were randomised to Phase III. Those allocated to the intervention completed Phase IV. Outcomes included: trial participation interest, desk-type (full desks/desk mounts) and assessment location (work/laboratory/home) preferences (Phase I); proportion of workspaces permitting sit-stand desk installation (Phase II); energy expenditure, sitting time and cardio-metabolic outcomes (Phase III); study participation experiences (Phase IV). Data were collected between May 2015 and December 2016. Recruitment and trial implementation were feasible: 92% of survey respondents expressed participation interest; 80% of workspaces could accommodate sit-stand desks; assessments were done in workplaces, preferred by 71%. Sit-stand desk provision reduced workplace sitting time by 94 min/day (95% CI 17.7–170.7). Their impact on energy expenditure and cardio-metabolic outcomes is unclear. The results confirm the feasibility of a trial assessing sit-stand desks' impact on energy expenditure, sitting time and cardio-metabolic outcomes, which should reduce uncertainty concerning the intervention's potential to reduce the health risks of prolonged sitting.Trial registration ISRCTN44827407. Keywords: Sit-stand desks, Standing desks, Height-adjustable desks, Sitting, Standing, Energy expenditure, Sedentary behaviour, Feasibility study

Sugar-sweetened beverages (SSBs) are one of the largest added sugar sources to diets in the UK and USA, particularly among young people. Warning labels, including calorie information labels, could reduce SSB consumption but uncertainty surrounds the labels that are most effective. This study assessed the impact of labels containing (a) each of two image-based warnings and (b) calorie information, singly and together, on SSB selection by parents of 11–16-year-olds living in the UK. Using a 3 (disease image, sugar content image, no image) × 2 (calorie information, no calorie information) between-subjects experimental design, 2002 participants were randomised to see beverages with one of six labels and selected one for their child to consume. The primary outcome was the proportion of participants selecting an SSB. Data were collected in December 2017. Logistic regressions showed SSB selection was lower when labels contained an image-based warning (35%), compared to not having any label (49%) or just calorie information (43.5%). The disease image lowered selection more than the sugar image (32% vs 40.5%). Providing calorie information with the disease image had no additional impact on selection (33%) but enhanced the impact of the sugar image (36%). Image-based warning labels discourage SSB selection by parents for their children. Images depicting health consequences of excess sugar consumption have larger effects than those depicting sugar content. Calorie information does not add to the effect of the former but does to that of the latter. Field studies are needed to assess the impact of SSB warning labels in real-life settings. Keywords: Warning labels, Calorie labels, Graphic warnings, Image-based labels, Energy information, Sugar-sweetened beverages, SSBs

Increasing the prices of products that harm health is an effective intervention for changing behaviour to improve health but public support for such interventions is generally low. The current paper investigates whether communicating evidence of a policy's effectiveness at tackling the focal problem could increase support. Across three studies we develop an infographic for communicating quantitative evidence of the effectiveness of a hypothetical tax to tackle childhood obesity. We investigate first, whether communicating evidence of effectiveness increases (a) perceived effectiveness (Studies 1,2,3) and (b) support for the policy, and second, whether any increase in perceived effectiveness mediates an increase in support (Studies 1 & 3). In all three studies (combined N = 9654) communicating evidence of effectiveness for the intervention increased perceived effectiveness. In Study 1, communicating evidence did not change support for the policy. Variations of the infographic were developed in Study 2 with one emerging as clearer and easier to comprehend. This infographic was therefore used in Study 3 in which it increased support for the tax from 45% to 49%, an effect that was mediated by perceived effectiveness. The effect sizes were small but probably meaningful at a population level. The results of these three studies suggest the potential for presenting quantitative evidence of intervention effectiveness to increase public support. Much uncertainty remains about the most effective ways of presenting this evidence, whether similar effects are achieved by presenting unquantified evidence and whether larger effects might be achieved by presenting information other than effectiveness.

Much of the global burden of non-communicable disease is caused by unhealthy behaviours that individuals enact even when informed of their health-harming consequences. A key insight is that these behaviours are not predominantly driven by deliberative conscious decisions, but occur directly in response to environmental cues and without necessary representation of their consequences. Consequently, interventions that target non-conscious rather than conscious processes to change health behaviour may have significant potential, but this important premise remains largely untested. This is in part due to the lack of a practicable conceptual framework that can be applied to better describe and assess these interventions. We propose a framework for describing or categorising interventions to change health behaviour by the degree to which their effects may be considered non-conscious. Potential practical issues with applying such a framework are discussed, as are the implications for further research to inform the testing and development of interventions. A pragmatic means of conceptualising interventions targeted at non-conscious processes is a necessary prelude to testing the potency of such interventions. This can ultimately inform the development of interventions with the potential to shape healthier behaviours across populations.

Lessons from a case of academic misconduct

Increasing the proportion of healthier foods available could encourage healthier consumption, but evidence to date is limited in scope and quality. The current study aimed to: (a) examine the feasibility and acceptability of intervening to change product availability in worksite cafeterias; and (b) estimate the impact on energy purchased of increasing the proportion of healthier (i.e. lower energy) cooked meals, snacks, cold drinks and sandwiches. Six English worksite cafeterias increased the proportion of healthier foods available, aiming to keep the total number of options constant, in a stepped wedge randomized controlled pilot trial conducted between January and May 2017. The intervention was generally successfully implemented and acceptable to clientele. Generalized linear mixed models showed a reduction of 6.9% (95%CI: -11.7%, -1.7%, p = 0.044) in energy (kcal) purchased from targeted food categories across all sites. However, impact varied across sites, with energy purchased from targeted categories significantly reduced in two sites (-10.7% (95%CI: -18.1% to -2.6%, p = 0.046); -18.4% (95%CI: -26.9% to -8.8%, p = 0.013)), while no significant differences were seen in the other four sites. Overall, increasing the proportion of healthier options available in worksite cafeterias seems a promising intervention to reduce energy purchased but contextual effects merit further study.

Background Reducing harmful consumption of food, alcohol, and tobacco products would prevent many cancers, diabetes and cardiovascular disease. Placing information-based cues in the environments in which we select and consume these products has the potential to contribute to changing these behaviours. Methods In this review, information-based cues are defined as those which comprise any combination of words, symbols, numbers or pictures that convey information about a product or its use. We specifically exclude cues which are located on the products themselves. We conducted a systematic review of randomised, cluster- randomised, and non-randomised controlled trials to assess the impact of such cues on selection and consumption. Thirteen studies met the inclusion criteria, of which 12 targeted food (most commonly fruit and vegetables), one targeted alcohol sales, and none targeted tobacco products. Results Ten studies reported statistically significant effects on some or all of the targeted products, although studies were insufficiently homogenous to justify meta-analysis. Existing evidence suggests information-based cues can influence selection and consumption of food and alcohol products, although significant uncertainty remains. Conclusions The current evidence base is limited both in quality and quantity, with relatively few, heterogeneous studies at unclear or high risk of bias. Additional, more rigorously conducted studies are warranted to better estimate the potential for these interventions to change selection and consumption of food, alcohol and tobacco products. Trial registration PROSPERO. 2016;CRD42016051884. Electronic supplementary material The online version of this article (10.1186/s12889-018-5280-5) contains supplementary material, which is available to authorized users.

Individual decision-makers need communications that succinctly describe potential harms and benefits of different options, but policymakers or citizens evaluating a policy are rarely given a balanced and easily understood summary of the potential outcomes of their decision. We review current policy option communication across diverse domains such as taxes, health, climate change, and international trade, followed by reviews of guidance and evidence for communication effectiveness. Our conceptual synthesis identifies four characteristics of policy options that make their communication particularly difficult: heterogeneous impacts on different segments of the population, multiple outcomes, long timescales, and large uncertainties. For communicators that are trying to inform rather than persuade, these complexities reveal a core tension between issue coverage and comprehensibility. We find little empirical evidence for how to communicate policy options effectively. We identify promising current communications, analyze them based on the above synthesis, and suggest priorities for future research. Recognizing the particular challenges of balanced, effective policy option communications could lead to better guidelines and support for policy decision-making.

Objectives Low alcohol labels are a set of labels that carry descriptors such as ‘low’ or ‘lighter’ to denote alcohol content in beverages. There is growing interest from policymakers and producers in lower strength alcohol products. However, there is a lack of evidence on how the general population perceives verbal descriptors of strength. The present research examines consumers’ perceptions of strength (% ABV) and appeal of alcohol products using low or high alcohol verbal descriptors. Design A within‐subjects experimental study in which participants rated the strength and appeal of 18 terms denoting low (nine terms), high (eight terms) and regular (one term) strengths for either (1) wine or (2) beer according to drinking preference. Methods Thousand six hundred adults (796 wine and 804 beer drinkers) sampled from a nationally representative UK panel. Results Low, Lower, Light, Lighter, and Reduced formed a cluster and were rated as denoting lower strength products than Regular, but higher strength than the cluster with intensifiers consisting of Extra Low, Super Low, Extra Light, and Super Light. Similar clustering in perceived strength was observed amongst the high verbal descriptors. Regular was the most appealing strength descriptor, with the low and high verbal descriptors using intensifiers rated least appealing. Conclusions The perceived strength and appeal of alcohol products diminished the more the verbal descriptors implied a deviation from Regular. The implications of these findings are discussed in terms of policy implications for lower strength alcohol labelling and associated public health outcomes.

Low self-control is associated with increased consumption of alcohol, tobacco, and unhealthy food. This systematic review aimed to assess whether individual differences in self-control modify the effectiveness of interventions to reduce consumption of these products, and hence their potential to reduce consumption amongst those whose consumption is generally greater. Searches of six databases were supplemented with snowball searches and forward citation tracking. Narrative synthesis summarised findings by: consumption behaviour (alcohol, tobacco, food); psychological processes targeted by the intervention (reflective, non-reflective, or both); and study design (experiment, cohort, or cross-sectional). Of 54 eligible studies, 22 reported no evidence of modification, 18 reported interventions to be less effective in those with low self-control, and 14 reported interventions to be more effective in those with low self-control. This pattern did not differ from chance. Whilst self-control often influenced intervention outcomes, there was no consistent pattern of effects, even when stratifying studies by consumption behaviour, intervention type, or study design. There was a notable absence of evidence regarding interventions that restructure physical or economic environments. In summary, a heterogeneous, low-quality evidence base suggests an inconsistent moderating effect of low self-control on the effectiveness of interventions to change consumption behaviours.

BACKGROUND: Unhealthy diet and low levels of physical activity are common behavioural factors in the aetiology of many non-communicable diseases. Recent years have witnessed an upsurge of policy and research interest in the use of taxes and other economic instruments to improve population health. OBJECTIVE: To assemble, configure and analyse empirical research studies available to inform the public health case for using economic instruments to promote dietary and physical activity behaviour change. METHODS: We conducted a systematic scoping review of evidence for the effects of specific interventions to change, or general exposure to variations in, prices or income on dietary and physical activity behaviours and corollary outcomes. Systematic electronic searches and parallel snowball searches retrieved >1 million study records. Text mining technologies were used to prioritise title-abstract records for screening. Eligible studies were selected, classified and analysed in terms of key characteristics and principal findings, using a narrative, configuring synthesis focused on implications for policy and further research. RESULTS: We identified 880 eligible studies, including 192 intervention studies and 768 studies that incorporated evidence for prices or income as correlates or determinants of target outcomes. Current evidence for the effects of economic instruments and exposures on diet and physical activity is limited in quality and equivocal in terms of its policy implications. Direct evidence for the effects of economic instruments is heavily skewed towards impacts on diet, with a relative lack of evidence for impacts on physical activity. CONCLUSIONS: The evidence-based case for using economic instruments to promote dietary and physical activity behaviour change may be less compelling than some proponents have claimed. Future research should include measurement of people's actual behavioural responses using study designs capable of generating reliable causal inferences regarding intervention effects. Policy implementation needs to be carefully aligned with evaluation planning and design.

BACKGROUND: The idea that behaviour can be influenced at population level by altering the environments within which people make choices (choice architecture) has gained traction in policy circles. However, empirical evidence to support this idea is limited, especially its application to changing health behaviour. We propose an evidence-based definition and typology of choice architecture interventions that have been implemented within small-scale micro-environments and evaluated for their effects on four key sets of health behaviours: diet, physical activity, alcohol and tobacco use. DISCUSSION: We argue that the limitations of the evidence base are due not simply to an absence of evidence, but also to a prior lack of definitional and conceptual clarity concerning applications of choice architecture to public health intervention. This has hampered the potential for systematic assessment of existing evidence. By seeking to address this issue, we demonstrate how our definition and typology have enabled systematic identification and preliminary mapping of a large body of available evidence for the effects of choice architecture interventions. We discuss key implications for further primary research, evidence synthesis and conceptual development to support the design and evaluation of such interventions. SUMMARY: This conceptual groundwork provides a foundation for future research to investigate the effectiveness of choice architecture interventions within micro-environments for changing health behaviour. The approach we used may also serve as a template for mapping other under-explored fields of enquiry.

OBJECTIVE: Labels indicating low/light versions of tobacco and foods are perceived as less harmful, which may encourage people to consume more. There is an absence of evidence concerning the impact on consumption of labeling alcohol products as lower in strength. The current study tests the hypothesis that labeling wine and beer as lower in alcohol increases their consumption. METHOD: Weekly wine and beer drinkers (n = 264) sampled from a representative panel of the general population of England were randomized to one of three groups to taste test drinks in a bar-laboratory varying only in the label displayed; Group 1: verbal descriptor Super Low combined with 4% alcohol by volume (ABV) for wine/1% ABV for beer; Group 2: verbal descriptor Low combined with 8% ABV for wine/3% ABV for beer; Group 3: no verbal descriptors of strength (Regular). Primary outcome was total volume (ml) of drink consumed. RESULTS: The results supported the study hypothesis: the total amount of drink consumed increased as the label on the drink denoted successively lower alcohol strength, BLin = .71, p = .015, 95% CI [0.13, 1.30]. Group contrasts showed significant differences between those offered drinks labeled as Super Low (M = 213.77) compared with Regular (M = 176.85), B = 1.43, p = .019, 95% CI [0.24, 2.61]. There was no significant difference in amount consumed between those offered drinks labeled as Low compared with Regular. CONCLUSIONS: These results suggest that labeling drinks as lower in strength increases the amount consumed. Further studies are warranted to test for replication in non-laboratory settings and to estimate whether any effects are at a level with the potential to harm health. TRIAL REGISTRATION: ISRCTN15530806. (PsycINFO Database Record

BackgroundTaxing soft-drinks may reduce their purchase, but assessing the impact on health demands wider consideration on alternative beverage choices. Effects on alcoholic drinks are of particular concern, as many contain similar or greater amounts of sugar than soft-drinks and have additional health harms. Changes in consumption of alcoholic drinks may reinforce or negate the intended effect of price changes for soft-drinks.MethodsA partial demand model, adapted from the Almost Ideal Demand System, was applied to Kantar Worldpanel data from 31 919 households from January 2012 to December 2013, covering drink purchases for home consumption, providing ~6 million purchases aggregated into 11 groups, including three levels of soft-drink, three of other non-alcoholic drinks and five of alcoholic drinks.ResultsAn increase in the price of high-sugar drinks leads to an increase in the purchase of lager, an increase in the price of medium-sugar drinks reduces purchases of alcoholic drinks, while an increase in the price of diet/low-sugar drinks increases purchases of beer, cider and wines. Overall, the effects of price rises are greatest in the low-income group.ConclusionIncreasing the price of soft-drinks may change purchase patterns for alcohol. Increasing the price of medium-sugar drinks has the potential to have a multiplier-effect beneficial to health through reducing alcohol purchases, with the converse for increases in the price of diet-drinks. Although the reasons for such associations cannot be explained from this analysis, requiring further study, the design of fiscal interventions should now consider these wider potential outcomes.

Background Nutritional labelling is advocated as a means to promote healthier food purchasing and consumption, including lower energy intake. Internationally, many different nutritional labelling schemes have been introduced. There is no consensus on whether such labelling is effective in promoting healthier behaviour. Objectives To assess the impact of nutritional labelling for food and non-alcoholic drinks on purchasing and consumption of healthier items. Our secondary objective was to explore possible effect moderators of nutritional labelling on purchasing and consumption. Search methods We searched 13 electronic databases including CENTRAL, MEDLINE and Embase to 26 April 2017. We also handsearched references and citations and sought unpublished studies through websites and trials registries. Selection criteria Eligible studies: were randomised or quasi-randomised controlled trials (RCTs/Q-RCTs), controlled before-and-after studies, or interrupted time series (ITS) studies; compared a labelled product (with information on nutrients or energy) with the same product without a nutritional label; assessed objectively measured purchasing or consumption of foods or non-alcoholic drinks in real-world or laboratory settings. Data collection and analysis Two authors independently selected studies for inclusion and extracted study data. We applied the Cochrane 'Risk of bias' tool and GRADE to assess the quality of evidence. We pooled studies that evaluated similar interventions and outcomes using a random-effects meta-analysis, and we synthesised data from other studies in a narrative summary. Main results We included 28 studies, comprising 17 RCTs, 5 Q-RCTs and 6 ITS studies. Most (21/28) took place in the USA, and 19 took place in university settings, 14 of which mainly involved university students or staff. Most (20/28) studies assessed the impact of labelling on menus or menu boards, or nutritional labelling placed on, or adjacent to, a range of foods or drinks from which participants could choose. Eight studies provided participants with only one labelled food or drink option (in which labelling was present on a container or packaging, adjacent to the food or on a display board) and measured the amount consumed. The most frequently assessed labelling type was energy (i.e. calorie) information (12/28). Eleven studies assessed the impact of nutritional labelling on purchasing food or drink options in real-world settings, including purchases from vending machines (one cluster-RCT), grocery stores (one ITS), or restaurants, cafeterias or coffee shops (three RCTs, one Q-RCT and five ITS). Findings on vending machines and grocery stores were not interpretable, and were rated as very low quality. A meta-analysis of the three RCTs, all of which assessed energy labelling on menus in restaurants, demonstrated a statistically significant reduction of 47 kcal in energy purchased (MD −46.72 kcal, 95% CI −78.35, −15.10, N = 1877). Assuming an average meal of 600 kcal, energy labelling on menus would reduce energy purchased per meal by 7.8% (95% CI 2.5% to 13.1%). The quality of the evidence for these three studies was rated as low, so our confidence in the effect estimate is limited and may change with further studies. Of the remaining six studies, only two (both ITS studies involving energy labels on menus or menus boards in a coffee shop or cafeteria) were at low risk of bias, and their results support the meta-analysis. The results of the other four studies which were conducted in a restaurant, cafeterias (2 studies) or a coffee shop, were not clearly reported and were at high risk of bias. Seventeen studies assessed the impact of nutritional labels on consumption in artificial settings or scenarios (henceforth referred to as laboratory studies or settings). Of these, eight (all RCTs) assessed the effect of labels on menus or placed on a range of food options. A meta-analysis of these studies did not conclusively demonstrate a reduction in energy consumed during a meal (MD −50 kcal, 95% CI −104.41, 3.88, N = 1705). We rated the quality of the evidence as low, so our confidence in the effect estimate is limited and may change with further studies. Six laboratory studies (four RCTs and two Q-RCTs) assessed the impact of labelling a single food or drink option (such as chocolate, pasta or soft drinks) on energy consumed during a snack or meal. A meta-analysis of these studies did not demonstrate a statistically significant difference in energy (kcal) consumed (SMD 0.05, 95% CI −0.17 to 0.27, N = 732). However, the confidence intervals were wide, suggesting uncertainty in the true effect size. We rated the quality of the evidence as low, so our confidence in the effect estimate is limited and may change with further studies. There was no evidence that nutritional labelling had the unintended harm of increasing energy purchased or consumed. Indirect evidence came from five laboratory studies that involved mislabelling single nutrient content (i.e. placing low energy or low fat labels on high-energy foods) during a snack or meal. A meta-analysis of these studies did not demonstrate a statistically significant increase in energy (kcal) consumed (SMD 0.19, 95% CI −0.14to 0.51, N = 718). The effect was small and the confidence intervals wide, suggesting uncertainty in the true effect size. We rated the quality of the evidence from these studies as very low, providing very little confidence in the effect estimate. Authors' conclusions Findings from a small body of low-quality evidence suggest that nutritional labelling comprising energy information on menus may reduce energy purchased in restaurants. The evidence assessing the impact on consumption of energy information on menus or on a range of food options in laboratory settings suggests a similar effect to that observed for purchasing, although the evidence is less definite and also of low quality. Accordingly, and in the absence of observed harms, we tentatively suggest that nutritional labelling on menus in restaurants could be used as part of a wider set of measures to tackle obesity. Additional high-quality research in real-world settings is needed to enable more certain conclusions. Further high-quality research is also needed to address the dearth of evidence from grocery stores and vending machines and to assess potential moderators of the intervention effect, including socioeconomic status. Nutritional labelling to promote healthier consumption and purchasing of food or drinks A poor diet including excessive energy intake is an important cause of ill health. Nutritional labelling may help people to make healthier food choices. What is the aim of this review? This review investigated whether nutritional labels (i.e. labels providing information about nutritional content) persuade people to buy or consume different (healthy) kinds of food. We searched for all available evidence to answer this question and found 28 studies. Key messages There is evidence to suggest that nutritional labelling, with energy information (e.g. calorie counts) on menus, may reduce energy purchased in restaurants, but more high-quality studies are needed to make this finding more certain. What was studied in the review? Some studies assessed buying food or drinks from vending machines, grocery stores, restaurants, cafeterias, or coffee shops. Others assessed the amount of food or drink consumed during a snack or meal in an artificial setting or scenario (referred to as laboratory studies or settings). What are the main results of the review? Nutritional labelling on restaurant menus reduced the amount of energy (i.e. calories) purchased, but the quality of the three studies that contributed to this finding was low, so our confidence in the effect estimate is limited and may change with further studies. Eight studies assessed this same type of intervention in laboratory settings, but instead of evaluating how much energy participants purchased, these studies evaluated how much energy participants consumed. These studies did not conclusively demonstrate a reduction in energy consumed when menus or foods were labelled, and they were also of low quality. In addition, six laboratory studies assessed how much energy participants consumed when they were given one food or drink option with or without labels, and five laboratory studies assessed how much energy participants consumed when foods were experimentally labelled as low energy or low fat when they were actually high-energy foods (i.e. mislabelling). Results from these two groups of studies were inconclusive and of low, or in the case of mislabelling studies, very low quality. We found some studies that assessed labelling on vending machines and grocery stores, but their results were not easy to interpret, so we could not use them to inform this review. How up-to-date is this review? The evidence is current to 26 April 2017.

Background Many interventions shown to be effective through clinical trials are not readily implemented in clinical practice. Unfortunately, little is known regarding how clinicians construct their perceptions of the effectiveness of medical interventions. This study aims to explore general practitioners' perceptions of the nature of 'effectiveness'. Methods The design was qualitative in nature using the repertory grid technique to elicit the constructs underlying the perceived effectiveness of a range of medical interventions. Eight medical interventions were used as stimuli (diclophenac to reduce acute pain, cognitive behaviour therapy to treat depression, weight loss surgery to achieve weight loss, diet and exercise to prevent type 2 diabetes, statins to prevent heart disease, stopping smoking to prevent heart disease, nicotine replacement therapy to stop smoking, and stop smoking groups to stop smoking). The setting involved face-to-face interviews followed by questionnaires in London Primary Care Trusts. Participants included a random sample of 13 general practitioners. Results Analysis of the ratings showed that the constructs clustered around two dimensions: low patient effort versus high patient effort (dimension one), and small impact versus large impact (dimension two). Dimension one represented constructs such as 'success requires little motivation', 'not a lifestyle intervention', and 'health-care professional led intervention'. Dimension two represented constructs such as 'weak and/or minimal evidence of effectiveness', 'small treatment effect for users', 'a small proportion of users will benefit' and 'not cost-effective'. Constructs within each dimension were closely related. Conclusions General practitioners judged the effectiveness of medical interventions by considering two broad dimensions: the extent to which interventions involve patient effort, and the size of their impact. The latter is informed by trial evidence, but the patient effort required to achieve effectiveness seems to be based on clinical judgement. Some of the failure of evidence-based medicine to be implemented may be more explicable if both dimensions were attended to.

Increased availability of low/er strength alcohol products has the potential to reduce alcohol consumption if they are marketed as substitutes for higher strength products rather than as additional products. The current study compares the main marketing messages conveyed by retailers and producers for low/er and regular strength wine and beer products. A content analysis of the marketing messages stated (in text) or depicted (in image) for low/er and regular strength wines and beers sold online on the websites of the four main UK retailers (Tesco, ASDA, Sainsbury’s, and Morrisons), and the producers of these products between February–March 2016. Four themes were identified: (a) suggested occasions for consumption, (b) health-related associations, (c) alcohol content, and (d) taste. Compared with regular strength products, low/er strength equivalents were more often marketed in association with occasions deemed to be suitable for their consumption including lunchtimes [wine: X 2 (1, n = 172) = 11.75, p = .001], outdoor events/barbeques [beer: X 2 (1, n = 96) = 11.16, p = .001] and on sport/fitness occasions [beer: X 2 (1, n = 96) = 7.55, p = .006]. Compared with regular strength wines and beers, low/er strength equivalents were more frequently marketed with images or text associated with health. These included images of fruit [wine: X 2 (1, n = 172) = 7.78, p = .005; beer: X 2 (1, n = 96) = 22.00, p

BACKGROUND: Understanding factors that influence public support for "nudging" policies, like pictorial cigarette pack warnings, may offer insight about how to increase such support. We sought to examine factors that influence smokers' support for requiring pictorial warnings on cigarette packs. METHODS: In 2014 and 2015, we randomly assigned 2149 adult US smokers to receive either pictorial warnings or text-only warnings on their cigarette packs for 4 weeks. The outcome examined in the current study was support for a policy requiring pictorial warnings on cigarette packs in the US. RESULTS: Support for pictorial warnings was high at baseline (mean: 3.2 out of 4). Exposure to pictorial warnings increased policy support at week 4 (β = .05, p = .03). This effect was explained by increases in perceived message effectiveness (p < .001) and reported conversations about policy support (p < .001). Message reactance (i.e., an oppositional reaction to the warning) partially diminished the impact of pictorial warnings on policy support (p < .001). CONCLUSIONS: Exposing people to a new policy through implementation could increase public support for that policy by increasing perceived effectiveness and by prompting conversations about the policy. Reactance may partially weaken the effect of policy exposure on public support.

OBJECTIVE: Placing snack-food further away from people consistently decreases its consumption ("proximity effect"). However, given diet-related health inequalities, it is important to know whether interventions that alter food proximity have potential to change behaviour regardless of cognitive resource (capacity for self-control). This is often lower in those in lower socio-economic positions, who also tend to have less healthy diet-related behaviours. Study 1 aims to replicate the proximity effect in a general population sample and estimate whether trait-level cognitive resource moderates the effect. In a stronger test, Study 2 investigates whether the effect is similar regardless of manipulated state-level cognitive resource. METHOD: Participants were recruited into two laboratory studies (Study 1: n = 159; Study 2: n = 246). A bowl of an unhealthy snack was positioned near (20 cm) or far (70 cm) from the participant, as randomised. In Study 2, participants were further randomised to a cognitive load intervention. The pre-specified primary outcome was the proportion of participants taking any of the snack. RESULTS: Significantly fewer participants took the snack when far compared with near in Study 2 (57.7% vs 70.7%, β = -1.63, p = 0.020), but not in Study 1 (53.8% vs 63.3%, X2 = 1.12, p = 0.289). Removing participants who moved the bowl (i.e. who did not adhere to protocol), increased the effect-sizes: Study 1: 39.3% vs 63.9%, X2 = 6.43, p = 0.011; Study 2: 56.0% vs 73.9%, β = -2.46, p = 0.003. Effects were not moderated by cognitive resource. CONCLUSIONS: These studies provide the most robust evidence to date that placing food further away reduces likelihood of consumption in general population samples, an effect unlikely to be moderated by cognitive resource. This indicates potential for interventions altering food proximity to contribute to addressing health inequalities, but requires testing in real-world settings. TRIAL REGISTRATION: Both studies were registered with ISRCTN (Study 1 reference no.: ISRCTN46995850, Study 2 reference no.: ISRCTN14239872).

Pharmacogenomics may improve health outcomes in two ways: by more precise and therefore more effective prescribing, tailored to genotype, and by increasing perceived effectiveness of treatments and so motivation for adherence. Little is known about patients' experiences of, and reactions to, receiving pharmacogenomically tailored treatments. The aim of this study was to explore the impact of pharmacogenomic prescribing of nicotine replacement therapy (NRT) on smokers' initial expectations of quit success, adherence, and perceived important differences from previous quit attempts. Semi-structured interviews were conducted with 40 smokers, purposively sampled from the Personalized Extra Treatment (PET) trial (ISRCTN 14352545). Together with NRT patches, participants were prescribed doses of oral NRT based on either mu-opioid receptor (OPRM1) genotype or nicotine dependence questionnaire score (phenotype). Data were analyzed using framework analysis, comparing views of participants in the two trial arms. Although most participants understood the basis for their prescribed NRT dose, it little influenced their views. The salient features of this quit attempt were the individualized behavioral support and combined NRT, not pharmacogenomic tailoring. Participants' initial expectations of success were mostly based on prior experiences of quitting. They attributed taking medication to nurse advice to do so, and attributed reducing or stopping it to side effects, forgetfulness, or practical difficulties. Intentional nonadherence appeared very rare. Pharmacogenomic NRT prescribing was not especially remarkable to participants and did not seem to influence adherence. Where services already tailor prescriptions to phenotype and provide individualized behavioral support for treatment adherence, pharmacogenomic prescribing may have limited additional benefit.

Most of us value our health highly yet act in ways that undermine it. If we ate and drank less, didn’t smoke, and were physically more active, 40% of cancers and 75% of diabetes and cardiovascular disease would be avoided. Because these behaviours tend to cluster by deprivation, achieving these changes for everyone could also halve the gaps in life expectancy and years lived in good health between the rich and the poor. In the UK, around 16% of the population smokes, the lowest figure for many decades, although among those who are poorest this rate is doubled. About 25% of those who consume alcohol do so at a rate considered harmful. Excessive eating explains much of why 65% of the population is overweight or obese. But our rates of inactivity top the lot: when measured objectively (rather than by our more generous self-reports) around 95% of us can be deemed “inactive” by failing to meet the guideline of 150 min of moderate intensity physical activity each week. Changing all these behaviours will need many different interventions operating at the same time. Critical will be the use of interventions that are effective at scale and with the potential to reach the entire population.

Sugar-sweetened beverage (SSB) consumption increases obesity risk and is linked to adverse health consequences. Large packages increase food consumption, but most evidence comes from studies comparing larger with standard packages, resulting in uncertainty regarding the impact of smaller packages. There is also little research on beverages. This qualitative study explores the experiences of consuming cola from smaller compared with larger bottles, to inform intervention strategies. Sixteen households in Cambridge, England, participating in a feasibility study assessing the impact of bottle size on in-home SSB consumption, received a set amount of cola each week for four weeks in one of four bottle sizes: 1500 ml, 1000 ml, 500 ml, or 250 ml, in random order. At the study end, household representatives were interviewed about their experiences of using each bottle, including perceptions of i) consumption level; ii) consumption-related behaviours; and iii) factors affecting consumption. Interviews were semi-structured and data analysed using the Framework approach. The present analysis focuses specifically on experiences relating to use of the smaller bottles. The smallest bottles were described as increasing drinking occasion frequency and encouraging consumption of numerous bottles in succession. Factors described as facilitating their consumption were: i) convenience and portability; ii) greater numbers of bottles available, which hindered consumption monitoring and control; iii) perceived insufficient quantity per bottle; and iv) positive attitudes. In a minority of cases the smallest bottles were perceived to have reduced consumption, but this was related to practical issues with the bottles that resulted in dislike. The perception of greater consumption and qualitative reports of drinking habits associated with the smallest bottles raise the possibility that the ‘portion size effect’ has a lower threshold, beyond which smaller portions and packages may increase consumption. This reinforces the need for empirical evidence to assess the in-home impact of smaller bottles on SSB consumption.