Evaluation of the impact of the Bristol’s outdoor advertisement restrictions policy on self-reported exposure to advertisements, consumption and use of unhealthy commodities.

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Genevieve Buckland, Zoi Toumpakari, Carlos Sillero-Rejon, Russ Jago, and 8 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7600850/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background Policies restricting advertisements of high fat, salt and sugar (HFSS) products and other unhealthy commodities are potentially effective tools to improve diet, reduce diet-related diseases and address public health inequalities. Bristol was the first UK city outside London to introduce such a policy on council-owned advertisement spaces in 2021. This study evaluates the policy’s impact on self-reported exposure to advertisements of HFSS products, alcohol and gambling, and self-reported consumption or use of these products. Methods A repeated cross-sectional survey of Bristol residents (intervention) and neighbouring South Gloucestershire residents (comparator) was administered before (n = 2,543) and after (n = 2,076) the policy was implemented. Self-reported exposure to outdoor adverts on HFSS products, alcohol and gambling in the local area and consumption or use of these products was collected, along with socio-demographic information. The intervention effect was analysed using a weighted controlled before-after design. Result Following the policy, there was no evidence of a change in self-reported exposure to advertising of unhealthy commodities, compared to the comparator group; percentage point change in exposure to advertising was − 6.9% (95% CI -34.9, 35.0) for any unhealthy commodity, -19.2% (95% CI -45.1, 17.4) for HFSS foods/drinks, 33.6% (95% CI -14.8, 100) for alcoholic drinks and − 8.6% (95% CI -38.1, 36.3) for gambling. Likewise, there were non-significant changes in self-reported consumption of HFSS products (-2.0% (95% CI -49.3, 89.6), alcohol (15.0% (95% CI -18.9, 64.9) and participation in gambling (-17.3% (95% CI -45.7, 25.9) following the introduction of the policy in Bristol, compared to comparators. Conclusions Following the implementation of the policy there was no measurable reduction in self-reported exposure to outdoor advertising of unhealthy commodities, nor was there much evidence of changes in reported consumption of HFSS products, alcohol or gambling. This may be attributable to the relatively small Council-owned outdoor advertisement estate (~ 30%), so changes in exposure may have been too small to lead to noticeable effects. However, this policy aligns with Bristol City Council’s ‘Health in all Policies’ approach aimed to support a systems-wide approach to improve health. Advertising HFSS Public Health Policy Evaluation Commercial determinants of health Figures Figure 1 Figure 2 Figure 3 Key Messages What is already known on this topic Policies restricting out of home (OOH) advertisements of unhealthy commodities are potentially effective tools which can be used by governments to reduce exposure to advertising of unhealthy commodities and in turn help address the commercial determinants of health. There is limited research into the effectiveness of such policy restrictions for reducing peoples perceived exposure to OOH advertisements of HFSS foods and drinks, alcohol, gambling, and consumption or use of these products. What this study adds This research found that following the implementation of a new policy in Bristol, restricting advertising of unhealthy commodities on council-owned outdoor spaces, there was no evidence of a measurable change in self-reported exposure to advertisements of unhealthy commodities, nor changes in consumption of HFSS products and alcohol or amount of gambling. How this study might affect research, practice or policy The lack of residents perceived changes in advertising of unhealthy commodities may be attributable to the relatively small council-owned OOH advertising estate within the total OOH advertising space. Future advertising restriction policies may need to be extended to cover more outdoor spaces and a wider variety of advertising platforms in order to sufficiently reduce unhealthy commodity advertising that people notice. Introduction Unhealthy diets, tobacco use and excessive alcohol consumption are amongst the key modifiable risk factors of non-communicable diseases (NCD), which in 2021 contributed to 43.8 million deaths and 1.73 billion disability adjusted life years worldwide[ 1 ]. The commercial determinants of health (CDoH) have been defined as ‘strategies and approaches used by the private sector to promote products and choices that are detrimental to health’[ 2 ]. Key drivers of the CDoH are industries which produce and market alcohol, tobacco and foods and drinks high in fat, salt or sugar (HFSS) and ultra-processed foods[ 2 ], and there is also an increasing awareness of other major health-harming industries such as gambling[ 3 ]. Extensive research shows that advertising and marketing of these products are related to their increased consumption[ 4 – 7 ], and greater exposure to gambling advertising leads to increased participation and risk of harmful effects[ 3 , 8 ]. Out of home (OOH) advertising is an important segment in the advertising industry, partly due to its high visibility and scope. It is estimated to reach 98% of the UK population at least once a week[ 9 ] and in 2023, outdoor advertising in the UK generated £1.3 billion in revenue [10] . OOH advertising includes adverts on bus shelters, billboards and transport facilities and is generally unavoidable whilst moving around towns and cities. This medium of advertising can be particularly effective at influencing shoppers purchasing decisions because adverts are often placed near locations where their products can be bought[ 7 ]. A sizable proportion of OOH advertising space in the UK is used to market unhealthy commodities. For example, surveys of bus shelter adverts in different regions of the UK reported that HFSS products account for 11–33% of adverts [11–13] . Perceived advertising of unhealthy foods/drinks (what people notice and recall) is also high; in London 51.5% of survey respondents reported seeing HFSS product advertising in functional environments and 36.4% across transport networks in the past week[ 14 ]. Perceived exposure to advertising can provide unique and relevant information which can complement research into actual OOH advertising displayed. For instance, previous research by our group showed that people who recalled seeing advertising for HFSS products in their local area (Bristol) were more likely to consume them, while this correlation was not evident with objectively measured adverts[ 15 ]. Policies restricting OOH advertisements of unhealthy commodities are potentially effective tools which can be used by governments to help address the CDoH, in particular dietary-related diseases[ 5 , 16 ]. In 2019, Transport for London (TfL) implemented a policy restricting advertising of HFSS products across their entire transport network, resulting in a 6.7% reduction in weekly household energy from HFSS products (-1,001.0kcal; 95% CI -1,546.0 to -456.0), an estimated 4.8% fewer individuals with obesity, and projected savings of £218 million by the NHS [17, 18] . The TfL policy may have served as a model for other areas and since its implementation numerous local authorities (LAs) in the UK have also put in places similar advertising restrictions on their publicly-owned advertising spaces [19, 20] . For example, in 2021 Bristol became the first city outside of London to introduce a similar policy [21] , but extended OOH advertisements restrictions to cover four key unhealthy commodities; HFSS products, alcoholic drinks, gambling and payday loans – tobacco advertising was already restricted on bus shelters. Although the policy applied to all Bristol city council owned advertising spaces, both online and physical, an important medium affected was bus shelters. Few studies have evaluated the overall impact of putting in place such OOH advertisement restriction policies, and to our knowledge none have assessed if they lead to a reduction in unhealthy commodity advertising that people notice or whether it leads to reduced consumption or use of these products. The Bristol Evaluation of Advertising Restrictions (BEAR) study evaluated the implementation and impact of Bristol’s advertising restriction policy using a mixed methods design[ 13 , 15 , 22 ]. A pre-policy resident’s survey conducted during baseline research within this study showed that in Bristol in the week prior to completing the survey, 66% of respondents reported seeing adverts of unhealthy commodities in their local area, 53% reporting seeing HFSS products advertised (the majority on bus shelters) and 88% of respondents reported consuming at least one HFSS product[ 13 , 15 ]. It also showed that self-reported exposure to OOH advertisement was moderately correlated with actual exposure, making this a useful metric for evaluation[ 15 ]. This study aims to assess if the policy resulted in a change in self-reported exposure to advertisements of HFSS foods and drinks, alcohol, gambling, and consumption or use of these products. Material and Methods The study protocol was published prior to the start of the analyses, and is available from Open Science Framework ( https://osf.io/24cyj ). The study received ethical approval by the University of Bristol Faculty of Health Sciences Research Ethics Committee (FREC) and was registered with the Open Science Framework. It is reported in accordance with STROBE guidelines (Online Supplementary Material (OSM) Table (T)1). Study design Self-reported information on exposure to OOH advertising of HFSS products, alcohol and gambling and consumption/use of these products was collected using repeated cross-sectional surveys. The surveys were completed by residents from Bristol (intervention) and the adjacent area of South Gloucestershire (SG) (comparator) before and after the Bristol advertising and sponsorship restrictions policy implementation. In both areas, a similar methodology was used to distribute the pre- and post-policy surveys. In Bristol, the surveys were distributed to approximately 4000 members of the council’s Citizen’s panel, newsletter subscribers and paper copies were also sent to the most deprived 20% of communities and provided at libraries, in order to capture digitally excluded citizens and other demographic groups. In SG, surveys were distributed to approximately 2,300 members of the council’s Viewpoint Panel, as well as paper copies at libraries. The survey questions and data collection processes have been published previously, and a sample survey can be found within the protocol’s appendix ( https://osf.io/24cyj )[ 13 , 15 ].They captured information on whether respondents had: i) been in their local area during the week prior to completing the survey and how much (all week, only a couple of days, away all week), ii) seen advertising for HFSS products, alcohol and gambling in their local area, iii) where they had seen the item advertised (i.e. on a billboard, bus shelter, side of a bus, side of a taxi or elsewhere), and iv) consumption/use of these products. The survey covered key HFSS product categories (biscuits & cakes, sugary cereals, chocolate & sweets, desserts, crisps & savoury snacks, fast-food, and sugary drinks) and included specific questions on types of fast-food chain adverts. The questions all related to exposure/consumption/use during the week prior to questionnaire completion and used multiple choice options. Additional questions asked about frequency of bus use and socio-demographic information. The baseline (pre-policy) survey was conducted between January and March 2022, which was after the policy’s inception date (November 2021), but prior to the advertising contracts ending and policy being practically implemented (first week of April 2022). The follow-up (post-policy) survey was conducted in the same period in 2023, after the policy came into effect. After the surveys were completed, the data were collated by Bristol and SG councils and postcodes were translated to Lower Super Output Areas (LSOAs) and anonymised, prior to sending it to the researchers. Respondents were classified as Bristol or SG residents based on their LSOAs, irrespective of which survey they completed. Because of anonymisation we were unable to identify residents who completed both the pre and post implementation surveys. The sample size was powered to detect > 5% absolute percentage point reduction in recent consumption of HFSS products, based on data obtained from the 2,560 responses from the baseline survey with 58% reporting consumption of HFSS foods in the previous 7 days. Statistical analysis The data were analysed using Stata version 15.1 (Stata Corporation, College Station, Texas). Index of multiple deprivation (IMD)[ 23 ] was mapped to respondents using their LSOAs[ 24 ]. Differences in the distribution of respondents characteristics (age group, sex, ethnicity, household occupancy, employment status, IMD decile and bus use) between the pre- and post-policy groups within each area were compared using chi-squared tests. The difference in prevalence of self-reported exposure to adverts or consumption/use of unhealthy commodities between pre- and post-policy surveys was calculated for Bristol and SG. The percentage change in exposure to advertisements or consumption/use of unhealthy commodities between pre- and post-policy groups was calculated and assessed using chi-squared tests. A controlled before-after design was used to analyse the average treatment effect on the treated - the estimated change in self-reported exposure to adverts of unhealthy commodities or consumption/use of unhealthy commodities in group of residents in Bristol. Four regression models were used with differing level of adjustments: unadjusted, adjusted for key confounders, additionally adjusted for entropy balancing weights (considered the primary analysis) and additionally adjusted for entropy balancing weights multiplied by population balancing weights. Confounding covariates included; sex (male, female), age (18–34, 35–44, 45–64 and ≥ 65 years), ethnicity (white, non-white), household occupancy (single, couple, family, shares and other), IMD (1–2, 3–4, 5–6, 7–8 and 9–10), and employment status (full time/part-time and self-employed, unemployed, retired and other). All covariates, except for IMD, had missing data (ranging from 0.6% to 3.1%) which were grouped into a missing category to maintain sample size. Entropy balancing weights[ 25 ] were calculated using the same confounding covariates listed above, such that the primary analysis was a doubly-robust model. A population weight variable was also created so that the gender ratio, age groups and ethnicity in each LSOA in the study population were balanced to match the distribution of these demographics within the source general population of Bristol and SG (calculated using information downloaded from the Office of National Statistics (ONS), 2020 Population Estimates Series). The regression models included a ‘timepoint’ variable (pre-policy and post-policy), an area variable (Bristol and SG) and an interaction term (area x timepoint). Main outcome variables were self-reported exposure to any advertisements of HFSS food/drinks, alcohol and gambling and consumption/use of HFSS foods/drinks, alcohol and gambling. Exposure to payday loans adverts was originally an outcome but since there were no adverts in this category either before or after the policy (ref pre-print paper), this outcome was dropped. The secondary outcome variables included the specific subcategories within these groups and where respondents saw the adverts. All outcomes were binary variables (yes/no) except for amount spent on gambling (categorical; £0-£10, >£10-£50, >£50-£100, >£100) and for frequency of consumption of HFSS foods and drinks (0, 1–3, 4–6 and 7 days a week). Regression beta-coefficients and 95% confidence intervals were converted to percentage point changes in exposure/consumption for ease of interpretation. Sensitivity Analyses Subgroup analyses were undertaken to explore potential differences in the ‘treatment effect’ by sex, age-group, ethnicity, IMD, bus use, amount of time in local area in the week before the survey and frequency of visits to the city centre. Finally, the main models were repeated while excluding; i) respondents who reported having only been in the local area for a couple of days in the past week, and ii) respondents with the highest and lowest IMD deciles; the latter because of significant differences in the distribution of IMD between the samples from the intervention and control groups at either end of the IMD range (Table 1 ). Results The final study sample, after exclusions, included 4,619 respondents, with 2,543 respondents from the pre-policy survey (n=1,110 from Bristol and n=1,433 from SG), and 2,076 respondents from the post-policy survey (n=711 from Bristol and n=1,365 from SG), (Figure 1). The majority of respondents were over 45 years old, of white ethnicity and female (Table 1). Compared to SG, respondents in Bristol were younger, more likely to live in deprived areas and were more likely to be in full time employment. The results across both areas showed that during the week prior to completing the survey, 58.2% of respondents reported seeing adverts of any unhealthy commodity and 39.7% reported seeing adverts for HFSS products (OSM T2). Self-reported exposure to advertising of any unhealthy commodity advert was higher in Bristol compared to SG; 66.0% and 66.5% in Bristol vs 52.2% and 53.9% in SG in pre- and post-policy survey responses, respectively (Figure 2A; OSM T2 & T3). In both pre-policy and post-policy surveys respectively, a higher proportion of respondents in Bristol compared to SG reported seeing adverts for any HFSS food/drink (52.6% and 50.5% in Bristol vs 31.0% and 32.8% in SG), with a similar pattern seen for HFSS food/drinks specifically marketed at children, fast-food chains, alcoholic drinks, and gambling companies). In contrast, a higher proportion of respondents in SG compared to Bristol reported seeing adverts for establishments serving alcohol (Figure 2A; OSM T2 & T3). For all the abovementioned exposures there was generally minimal changes between pre- and post-policy responses within each area. Within the HFSS food/drinks advert groups, fast-food adverts were most commonly reported across both areas (33.1%), followed by sugary drinks (14.8%) and chocolate and sweets (14.5%), with a higher exposure reported in Bristol compared to SG in both pre- and post-policy surveys (Figure 2B; OSM T2 & T3). In contrast, self-reported consumption of any HFSS foods/drink was higher in SG than Bristol (93.0% and 93.8% in SG vs 87.5% and 86.8% in Bristol, pre-policy and post-policy survey respectively),(Figure 2C; OSM T4 & T5). In Bristol, reported alcohol consumption was generally lower in the post-policy compared to pre-policy survey, but consumption of HFSS products and gambling activity were generally comparable (Figure 2E and 2D, OSM T4 & T5). The most common places respondents reported seeing the unhealthy commodity adverts were on billboards, bus shelters and sides of buses (Figure 3). In Bristol, the proportion of HFSS products, gambling and alcohol adverts seen on bus shelters was significantly lower after the policy compared to before, while this pattern was not evident in SG (Figure 4, OSM T6). Following the implementation of the policy, there was barely any change in self-reported exposure to adverts of any unhealthy commodity in the doubly robust model; -6.9% (95% CI -34.9, 35.0) percentage point reduction compared to comparator group (Table 2). There was also no evidence of changes in reported exposure to the different categories of unhealthy commodity adverts; percentage point change in reported exposure was -19.2% (95% CI -45.1,17.4) for HFSS foods/drink adverts, 33.6% (95% CI -14.8, 100.0) for alcoholic drinks adverts and -8.6% (95% CI -38.1, 36.3) for gambling adverts (Table 2). For HFSS product subgroups, the majority of the point estimates were negative, representing a reduction in reported exposure, albeit non-significant (Table 3). There were generally minimal differences between the estimates derived from crude and doubly robust models for the main unhealthy commodity advert groups (Table 2), or when models were additionally adjusted for population weighting (OSM T7-T9). Although there were reductions following the policy in any gambling activity (-17.3% (95% CI -45.7, 25.9), consumption of any HFSS product (-2.0% (95% CI -49.3, 89.6) and most HFSS product subgroups, in Bristol compared to comparators, none of these reached statistical significance (Table 3 and OSM T9). In secondary analyses, repeating the main models stratified by respondents’ characteristics, there was no evidence of changes in reported exposure any advert of unhealthy commodities or consumption of unhealthy commodities within different respondent subgroups (Table 4). In analyses stratified by location of observed adverts, there was no evidence of a change in reported exposure to adverts of HFSS products seen at bus shelters or other advertising sites (data not tabulated). In sensitivity analyses excluding respondents in the top and bottom IMD from the analysis, the change in reported exposure to any unhealthy commodity advert (β -0.5 (95% CI -1.1, 0.1) and consumption of any HFSS food/drink (β -0.2 (95% CI -1.1, 0.7) in Bristol compared to the comparator group was comparable to the analysis of the full sample (data not tabulated). Discussion This study aimed to evaluate the perceived change in advertising of unhealthy foods/drinks, alcohol and gambling, as well as any change in consumption or use of these commodities, after the implementation of a new advertisement restriction policy in Bristol in 2022. The findings indicate little evidence of changes in self-reported exposure to advertisements of unhealthy commodities in Bristol, or changes in consumption of HFSS products and alcohol or participation in gambling, following implementation of the policy. However, it is noteworthy that for HFSS products (exposure and consumption), the observed changes following the policy implementation were in the hypothesised direction. There are several potential explanations for these findings. Firstly, the study may have been underpowered, particularly because the post-policy survey group in Bristol (the exposed arm) had approximately half the number of respondents than the pre- and post-policy comparator group, which was due to lower participation rates. In addition, although entropy weights were used to balance out the socio-demographic differences between respondents in Bristol and SG (particularly IMD levels between the areas), residual confounding cannot be ruled out. Another explanation is that the advertising restrictions only affected a relatively small proportion of total OOH advertisement space within Bristol, because the policy only applied to council-owned advertising spaces (283 bus shelters). In line with this residents reported seeing advertisements of unhealthy commodities (including HFSS products) on many other OOH spaces which were not subject to the policy because they were commercially owned (i.e. billboards and buses). In addition, our previous research showed that before the policy was implemented only 11% of bus shelter advertisements in Bristol displayed non-compliant unhealthy commodities (ref pre-print paper), indicating the baseline level of exposure to unhealthy advertising on bus shelters was already low. This may have been further compounded by the knock-on effects of the Covid-19 pandemic, which resulted in reductions in transport use due to more people working from home[ 26 ]. Collectively, these factors suggest that any change in exposure to OOH advertising of unhealthy commodities as a result of the policy may have been too small (relative to the total OOH advertising environment) to lead to noticeable and measurable changes. Our findings also align with another arm of the BEAR study evaluating changes in household purchasing data, which found no evidence of a change in household purchasing of HFSS products in Bristol following the policy (ref pre-print paper). To the best of our knowledge, there are no directly comparable studies assessing changes in perceived exposure to OOH unhealthy commodity advertising following advertising restriction policies. However, we can compare our results on overall exposure to unhealthy commodity advertising to other research on OOH advertising exposure. For instance, our findings on self-reported exposure to HFSS products were similar to that observed in the TfL evaluation[ 14 ], with 36% of participants reporting to have seen HFSS advertising on transport networks in the past week in London, which is comparable to 39% in our study (for Bristol and SG). Respondents in London with a lower socioeconomic position were more likely to report seeing OOH advertisements of unhealthy foods/drinks[ 14 ]. In the pre-policy baseline data from our study respondents from more deprived areas, compared to less deprived areas, also observed more unhealthy commodity advertising, particularly for HFSS products[ 13 ]. It would be logical to hypothesise that this group of respondents could be more likely to notice changes in advertising resulting from the policy, due to greater overall exposure, however in stratified analyses by area-level deprivation there was no evidence of this. Likewise, there was no evidence of a reduction in exposure to unhealthy commodity adverts for respondents who used buses regularly (daily or several times a week). The strengths of the study include the relatively large sample size, which despite having a smaller number of responses than expected in Bristol after the implementation of the policy, still included over 4,500 respondents from Bristol and the comparator area. In addition, specific strategies were used to try and include harder-to-reach individuals, for example, by providing paper copies and distributing surveys via libraries. Since the demographic profile of the surveyed residents in Bristol and SG were not directly comparable to the general population (the surveyed sample had a higher percentage of women and older people), we used a population weighting variable in an additional analysis to balance these demographics to the general population. However, there were minimal changes in the results even after adjusting for population weighting. Another strength is that we were able to explore if the results differed for the subgroup of respondents who were in the area the entire week and those who specifically used public transport (these showed similar findings to the main analysis). The study has several limitations, firstly advertising exposure was based on self-reported information and so would be susceptible to measurement error[ 27 ]. A related limitation is that information on consumption of HFSS products and alcohol was based on recalling which types of HFSS products and alcoholic drinks had been consumed in the past week and over how many days. This data is also likely to be subject to measurement error, including recall and social desirability bias. We aimed to reduce this source of measurement error by only asking about exposure and consumption in the past week. This may mean that the reported exposure and consumption was not representative of habitual exposure and consumption. Furthermore, some respondents will have travelled outside of their immediate neighbourhood during the past week, so when asked about what adverts they have seen in their local area (their street and surrounding streets), it is possible that some respondents may have unintentionally reported adverts they saw in other areas. There were also socio-demographic differences between respondents from Bristol and SG, with more respondents from Bristol having a lower IMD and being in full time employment. In part this may have resulted from differences in the sampling strategies in both areas. However, entropy balancing weights were used in the regression models, and sensitivity analyses excluded the extreme IMDs to try and address these differences. A further limitation is that we did not capture information on intensity of exposure to unhealthy commodity adverts before and after the policy, as the survey questions focused on whether residents had seen any advertising of HFSS products in their local area, classifying participants as exposed or not. This was a deliberate choice as asking residents how many adverts of unhealthy commodities they had seen in the past week would have likely introduced additional measurement error. Therefore, although there was no evidence of a reduction in seeing any HFSS product adverts following the policy, there could have been a reduction in the number of HFSS products adverts observed (intervention dose) which was not captured. Indeed, the in-person audit of actual advertising displayed on bus shelters in Bristol before and after the policy’s implementation showed there was a substantial reduction in number of adverts of unhealthy commodities, falling from 11% of all advertising before to 0.8% after the policy, mainly due to a reduction in adverts for HFSS products (ref pre-print paper). Regardless, when we assessed the change in self-reported exposure to adverts of HFSS products specifically seen at bus shelters, there was still no evidence of a reduction in exposure following the policy. However, it should be noted that in baseline research within the BEAR study there was a significant association between measured exposure of HFSS product adverts (through in-person audits) and self-reported exposure, particularly for exposure at bus shelters (reporting ratio (RR) of 1.68; 95% CI 1.40 to 2.03)[ 15 ]. Finally, we could not calculate the response rates as we didn’t have information on how many people saw the surveys in libraries for example, or when they stopped being available. Despite finding no clear evidence of changes in self-reported exposure to adverts of unhealthy commodities, the policy aligns with the council’s ‘health in all policies’ initiative. This supports their drive to deliver clear and consistent messaging regarding public health issues with the overarching aim to improve the health of all residents, as reported in the qualitative evaluation of the policy implementation (ref pre-print paper). As additional regions across the UK implement similar policies the number of OOH unhealthy product adverts that people see should progressively decline[ 20 , 28 , 29 ]. However, OOH advertising only contributes to a relatively minor portion of where people see unhealthy commodity advertising, with advertising on online platforms becoming increasingly prevalent[ 5 ]. Research indicates that advertising restrictions which target a wide range of settings are more likely to have a greater impact, partly because companies can adapt to partial bans by refocusing advertising to non-restricted media to reach their target audience[ 30 , 31 ]. This is particularly relevant when tackling childhood obesity, because of concerns that children are more susceptible to the persuasive intent of food marketing[ 6 , 32 ], which often promote energy-dense, nutrient-poor products[ 7 , 33 ]. Indeed, in the UK, a third of food and soft drink advertising expenditure is for marketing confectionery, snacks, desserts and soft drinks compared to only 1% for fruit and vegetables[ 34 ]. Evidence also suggests that nation-wide mandatory regulations are likely to be more effective than voluntary policies[ 31 ]. Therefore, policies which restrict advertising of unhealthy commodities, including OOH settings, can been seen as part of a series of strategies to address the CDoH and their negative impact on NCDs and quality of life[ 5 , 19 , 35 ]. In conclusion, our findings suggest that following implementation of a new advertisement and sponsorship policy restricting advertisement of unhealthy commodities on Council-owned spaces in Bristol, there was no measurable significant change in residents reporting being exposed to OOH advertising of unhealthy commodities, nor evidence of significant changes in self-reported consumption of HFSS products, alcohol or participating in gambling. Future advertising restriction policies may need to be extended to cover more outdoor spaces and a wider variety of advertising platforms in order to sufficiently reduce unhealthy commodity advertising that people notice. However, the optimal intervention dose is still unknown and warrants further research, along with the potential impact this could have on population health and healthcare cost savings. Declarations The participants consented to participate in the study." Funding: This project is funded by the National Institute for Health and Care Research [Public Health Research Programme – project 152114]. LJS, CSR, RB, SH and GB and JH are funded by the National Institute for Health and Care Research Applied Research Collaboration West (NIHR ARC West). FDV, RJ and WH are partly funded by NIHR ARC West. The views and opinions expressed herein are those of the authors and do not necessarily reflect those of the NIHR PHR Programme, NIHR or the Department of Health and Social Care. Funders had no involvement in data analysis, data interpretation or writing of the paper. Acknowledgements: The authors would like to thank Bristol City Council and South Gloucestershire Council for their support in the design and implementation of the BEAR study, as well as Bristol, North Somerset and South Gloucestershire NHS Integrated Care Board. We would also like to thank all the members of the Study Oversight Group. Finally, we would like to thank all the participants from Bristol and South Gloucestershire who filled out the resident surveys. References Li J, Pandian V, Davidson PM, Song Y, Chen N, Fong DYT: Burden and attributable risk factors of non-communicable diseases and subtypes in 204 countries and territories, 1990-2021: a systematic analysis for the global burden of disease study 2021 . Int J Surg 2025, 111 (3):2385-2397. Kickbusch I, Allen L, Franz C: The commercial determinants of health . Lancet Glob Health 2016, 4 (12):e895-e896. Goyder E, Blank L, Baxter S, van Schalkwyk MC: Tackling gambling related harms as a public health issue . 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Scott LJ, Nobles J, Sillero-Rejon C, Brockman R, Toumpakari Z, Jago R, Cummins S, Blake S, Horwood J, de Vocht F: Advertisement of unhealthy commodities in Bristol and South Gloucestershire and rationale for a new advertisement policy . BMC Public Health 2023, 23 (1):1078-1090. Yau A, Adams J, Boyland EJ, Burgoine T, Cornelsen L, de Vocht F, Egan M, Er V, Lake AA, Lock K et al : Sociodemographic differences in self-reported exposure to high fat, salt and sugar food and drink advertising: a cross-sectional analysis of 2019 UK panel data . BMJ Open 2021, 11 (4):e048139. Scott LJ, Toumpakari Z, Nobles J, Sillero-Rejon C, Jago R, Cummins S, Blake S, Horwood J, Vocht F: Assessing exposure to outdoor advertisement for products high in fat, salt and sugar (HFSS); is self-reported exposure a useful exposure metric? BMC Public Health 2023, 23 (1):668-679. WHO. Implementation roadmap 2023–2030 for the Global action plan for the prevention and control of NCDs 2013–2030. Geneva (Switzerland): WHO; 2021 . Yau A, Berger N, Law C, Cornelsen L, Greener R, Adams J, Boyland EJ, Burgoine T, de Vocht F, Egan M et al : Changes in household food and drink purchases following restrictions on the advertisement of high fat, salt, and sugar products across the Transport for London network: A controlled interrupted time series analysis . PLoS Med 2022, 19 (2):e1003915. Thomas C, Breeze P, Cummins S, Cornelsen L, Yau A, Brennan A: The health, cost and equity impacts of restrictions on the advertisement of high fat, salt and sugar products across the transport for London network: a health economic modelling study . Int J Behav Nutr Phys Act 2022, 19 (1):93-105. Healthier food advertising policies [https://www.sustainweb.org/commercial-determinants/healthier-food-advertising-policies/] McKevitt S, White M, Petticrew M, Summerbell C, Vasiljevic M, Boyland E, Cummins S, Laverty AA, Millett C, de Vocht F et al : Characterizing restrictions on commercial advertising and sponsorship of harmful commodities in local government policies: a nationwide study in England . J Public Health (Oxf) 2023, 45 (4):878-887. Bristol City Council (BCC). Advertising and Sponsorship Policy [https://democracy.bristol.gov.uk/documents/s58004/Appendix%20Ai%20-%20Advertising%20and%20Sponsorship%20Policy.pdf] The Bristol Evaluation of Advertising Restrictions Study (BEAR study). [https://arc-w.nihr.ac.uk/research/projects/bristol-advertising-restrictions-evaluation/] Ministry of Housing, Communities & Local Government (2018 to 2021). English indices of deprivation 2019 [https://www.gov.uk/government/statistics/english-indices-of-deprivation-2019] Office for National Statistics (ONS). Statistical geographies: An overview of the statistical geographies in the four countries of the UK. [https://www.ons.gov.uk/methodology/geography/ukgeographies/statisticalgeographies] Hainmueller J: Entropy Balancing for Causal Effects: A Multivariate Reweighting Method to Produce Balanced Samples in Observational Studies . Political Analysis 2017, 20 (1):25-46. Department for Transport. National Travel Survey 2023: Trends in public transport use and multi-modal public transport trips. Published in 2024. [https://www.gov.uk/government/statistics/national-travel-survey-2023/nts-2023-trends-in-public-transport-use-and-multi-modal-public-transport-trips] Nieuwenhuijsen M (ed.): Questionnaires. In: Nieuwenhuijsen M, Editor. Exposure assessment in environmental epidemiology. 2ed. : New York: Oxford University Press; 2015. Sykes S, Watkins M, Bond M, Jenkins C, Wills J: What works in advocating for food advertising policy change across an english region - a realist evaluation . BMC Public Health 2023, 23 (1):1896. Reynolds B, Holt A, Bernhardt F, et al. Taking down junk food ads. 2019. [.https://www.sustainweb.org/publications/taking_down_junk_food_ads/] Alfraidi A, Alafif N, Alsukait R: The Impact of Mandatory Food-Marketing Regulations on Purchase and Exposure: A Narrative Review . Children (Basel) 2023, 10 (8):1277-1288. Kovic Y, Noel JK, Ungemack JA, Burleson JA: The impact of junk food marketing regulations on food sales: an ecological study . Obes Rev 2018, 19 (6):761-769. Norman J, Kelly B, Boyland E, McMahon A-T: The Impact of Marketing and Advertising on Food Behaviours: Evaluating the Evidence for a Causal Relationship . Current Nutrition Reports 2016, 5 (3):139-149. Dhar T, Baylis K: Fast-Food Consumption and the Ban on advertising targeting children_the quebec experience. Journal of Marketing Research 2011, 48 :799–813. The Food Foundation. The Broken Plate. London 2023. [https://foodfoundation.org.uk/sites/default/files/2023-10/TFF_The%20Broken%20Plate%202023_Digital_FINAL..pdf] Popkin BM, Adair LS, Ng SW: Global nutrition transition and the pandemic of obesity in developing countries . Nutr Rev 2012, 70 (1):3-21. Tables Tables 1 to 4 are available in the Supplementary Files section. Additional Declarations The authors declare no competing interests. Supplementary Files BEARstudyWP2Suppl.materialpreprint.docx Evaluation of the impact of the Bristol’s outdoor advertisement restrictions policy on self-reported exposure to advertisements, consumption and use of unhealthy commodities_Supplementary Material Table1234.docx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7600850","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":514221974,"identity":"03ea7a35-74e8-4aa2-893c-b79d8cf00cb1","order_by":0,"name":"Genevieve Buckland","email":"","orcid":"https://orcid.org/0000-0003-2060-6598","institution":"University of Bristol","correspondingAuthor":false,"prefix":"","firstName":"Genevieve","middleName":"","lastName":"Buckland","suffix":""},{"id":514221975,"identity":"b3420fc6-ae21-4447-a944-bbc75177a6cd","order_by":1,"name":"Zoi Toumpakari","email":"","orcid":"","institution":"University of Bristol","correspondingAuthor":false,"prefix":"","firstName":"Zoi","middleName":"","lastName":"Toumpakari","suffix":""},{"id":514221976,"identity":"045a1792-6668-4731-bf2c-8d6615b47d1c","order_by":2,"name":"Carlos Sillero-Rejon","email":"","orcid":"","institution":"University of Bristol","correspondingAuthor":false,"prefix":"","firstName":"Carlos","middleName":"","lastName":"Sillero-Rejon","suffix":""},{"id":514221977,"identity":"f221efed-ab11-430d-884a-d1f94fdec845","order_by":3,"name":"Russ Jago","email":"","orcid":"","institution":"University of Bristol","correspondingAuthor":false,"prefix":"","firstName":"Russ","middleName":"","lastName":"Jago","suffix":""},{"id":514221978,"identity":"72575569-6153-4200-937f-c689c1ea1572","order_by":4,"name":"Steve Cummins","email":"","orcid":"","institution":"London School of Hygiene and Tropical 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13:01:43","currentVersionCode":1,"declarations":{"humanSubjects":true,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":true,"humanSubjectConsent":true,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-7600850/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7600850/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":91442160,"identity":"64d5415e-2f8e-4003-bcd8-18491f22d3c7","added_by":"auto","created_at":"2025-09-16 14:18:06","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":213210,"visible":true,"origin":"","legend":"\u003cp\u003eStudy flow diagram for participants completing the surveys in Bristol and South Gloucestershire.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7600850/v1/fd9ae17655b45ee0bd1ff5ac.png"},{"id":91444090,"identity":"2fe1bfb2-94d2-4c18-a10e-d0c6c2443c35","added_by":"auto","created_at":"2025-09-16 14:26:06","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":138960,"visible":true,"origin":"","legend":"\u003cp\u003ePercentage of respondents reporting exposure to unhealthy commodity advertising before and after the policy.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7600850/v1/34f2f1b45ea618cb074a0fab.png"},{"id":91444094,"identity":"80792547-c364-4252-a918-0ceeec6e7b25","added_by":"auto","created_at":"2025-09-16 14:26:06","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":155545,"visible":true,"origin":"","legend":"\u003cp\u003eProportion of unhealthy commodity adverts seen in different OOH locations by respondents.\u003c/p\u003e\n\u003cp\u003eFootnotes:\u003cstrong\u003e \u003c/strong\u003e*Denotes difference between proportions pre- and post-policy survey (within respective \u0026nbsp;area) was statistically significant at p\u0026lt;0.05\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7600850/v1/cf8a206870d1f0322584b0c1.png"},{"id":91446796,"identity":"9b2f84a7-e631-4dc5-b76f-02f9b2bfb740","added_by":"auto","created_at":"2025-09-16 14:50:07","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2684898,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7600850/v1/5be94c95-9eea-4e9e-8304-6cb0f8c0f5ba.pdf"},{"id":91442163,"identity":"4533a9ce-86e3-47c3-9d26-fc23b94c0b6d","added_by":"auto","created_at":"2025-09-16 14:18:06","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":117317,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eEvaluation of the impact of the Bristol’s outdoor advertisement restrictions policy on self-reported exposure to advertisements, consumption and use of unhealthy commodities_Supplementary Material\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"BEARstudyWP2Suppl.materialpreprint.docx","url":"https://assets-eu.researchsquare.com/files/rs-7600850/v1/4e7960732968e7d1616104c9.docx"},{"id":91444089,"identity":"998e9bcd-9a47-4719-ba2d-bf1993fed08e","added_by":"auto","created_at":"2025-09-16 14:26:06","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":47594,"visible":true,"origin":"","legend":"","description":"","filename":"Table1234.docx","url":"https://assets-eu.researchsquare.com/files/rs-7600850/v1/95d6ec081ba1d540a27e6579.docx"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003eEvaluation of the impact of the Bristol’s outdoor advertisement restrictions policy on self-reported exposure to advertisements, consumption and use of unhealthy commodities.\u003c/p\u003e","fulltext":[{"header":"Key Messages ","content":"\u003cp\u003e\u003cstrong\u003eWhat is already known on this topic\u003c/strong\u003e\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003ePolicies restricting out of home (OOH) advertisements of unhealthy commodities are potentially effective tools which can be used by governments to reduce exposure to advertising of unhealthy commodities and in turn help address the commercial determinants of health.\u003c/li\u003e\n \u003cli\u003eThere is limited research into the effectiveness of such policy restrictions for reducing peoples perceived exposure to OOH advertisements of HFSS foods and drinks, alcohol, gambling, and consumption or use of these products.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003eWhat this study adds\u003c/strong\u003e\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eThis research found that following the implementation of a new policy in Bristol, restricting advertising of unhealthy commodities on council-owned outdoor spaces, there was no evidence of a measurable change in self-reported exposure to advertisements of unhealthy commodities, nor changes in consumption of HFSS products and alcohol or amount of gambling.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003eHow this study might affect research, practice or policy\u003c/strong\u003e\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003eThe lack of residents perceived changes in advertising of unhealthy commodities may be attributable to the relatively small council-owned OOH advertising estate within the total OOH advertising space.\u003c/li\u003e\n \u003cli\u003eFuture advertising restriction policies may need to be extended to cover more outdoor spaces and a wider variety of advertising platforms in order to sufficiently reduce unhealthy commodity advertising that people notice.\u003c/li\u003e\n\u003c/ul\u003e"},{"header":"Introduction","content":"\u003cp\u003eUnhealthy diets, tobacco use and excessive alcohol consumption are amongst the key modifiable risk factors of non-communicable diseases (NCD), which in 2021 contributed to 43.8\u0026nbsp;million deaths and 1.73\u0026nbsp;billion disability adjusted life years worldwide[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. The commercial determinants of health (CDoH) have been defined as \u0026lsquo;strategies and approaches used by the private sector to promote products and choices that are detrimental to health\u0026rsquo;[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Key drivers of the CDoH are industries which produce and market alcohol, tobacco and foods and drinks high in fat, salt or sugar (HFSS) and ultra-processed foods[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], and there is also an increasing awareness of other major health-harming industries such as gambling[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Extensive research shows that advertising and marketing of these products are related to their increased consumption[\u003cspan additionalcitationids=\"CR5 CR6\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e], and greater exposure to gambling advertising leads to increased participation and risk of harmful effects[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eOut of home (OOH) advertising is an important segment in the advertising industry, partly due to its high visibility and scope. It is estimated to reach 98% of the UK population at least once a week[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e] and in 2023, outdoor advertising in the UK generated \u0026pound;1.3\u0026nbsp;billion in revenue\u003csup\u003e[10]\u003c/sup\u003e. OOH advertising includes adverts on bus shelters, billboards and transport facilities and is generally unavoidable whilst moving around towns and cities. This medium of advertising can be particularly effective at influencing shoppers purchasing decisions because adverts are often placed near locations where their products can be bought[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eA sizable proportion of OOH advertising space in the UK is used to market unhealthy commodities. For example, surveys of bus shelter adverts in different regions of the UK reported that HFSS products account for 11\u0026ndash;33% of adverts\u003csup\u003e[11\u0026ndash;13]\u003c/sup\u003e. Perceived advertising of unhealthy foods/drinks (what people notice and recall) is also high; in London 51.5% of survey respondents reported seeing HFSS product advertising in functional environments and 36.4% across transport networks in the past week[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Perceived exposure to advertising can provide unique and relevant information which can complement research into actual OOH advertising displayed. For instance, previous research by our group showed that people who recalled seeing advertising for HFSS products in their local area (Bristol) were more likely to consume them, while this correlation was not evident with objectively measured adverts[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e\u003cp\u003ePolicies restricting OOH advertisements of unhealthy commodities are potentially effective tools which can be used by governments to help address the CDoH, in particular dietary-related diseases[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. In 2019, Transport for London (TfL) implemented a policy restricting advertising of HFSS products across their entire transport network, resulting in a 6.7% reduction in weekly household energy from HFSS products (-1,001.0kcal; 95% CI -1,546.0 to -456.0), an estimated 4.8% fewer individuals with obesity, and projected savings of \u0026pound;218\u0026nbsp;million by the NHS\u003csup\u003e[17, 18]\u003c/sup\u003e. The TfL policy may have served as a model for other areas and since its implementation numerous local authorities (LAs) in the UK have also put in places similar advertising restrictions on their publicly-owned advertising spaces\u003csup\u003e[19, 20]\u003c/sup\u003e. For example, in 2021 Bristol became the first city outside of London to introduce a similar policy\u003csup\u003e[21]\u003c/sup\u003e, but extended OOH advertisements restrictions to cover four key unhealthy commodities; HFSS products, alcoholic drinks, gambling and payday loans \u0026ndash; tobacco advertising was already restricted on bus shelters. Although the policy applied to all Bristol city council owned advertising spaces, both online and physical, an important medium affected was bus shelters.\u003c/p\u003e\u003cp\u003eFew studies have evaluated the overall impact of putting in place such OOH advertisement restriction policies, and to our knowledge none have assessed if they lead to a reduction in unhealthy commodity advertising that people notice or whether it leads to reduced consumption or use of these products. The Bristol Evaluation of Advertising Restrictions (BEAR) study evaluated the implementation and impact of Bristol\u0026rsquo;s advertising restriction policy using a mixed methods design[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. A pre-policy resident\u0026rsquo;s survey conducted during baseline research within this study showed that in Bristol in the week prior to completing the survey, 66% of respondents reported seeing adverts of unhealthy commodities in their local area, 53% reporting seeing HFSS products advertised (the majority on bus shelters) and 88% of respondents reported consuming at least one HFSS product[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. It also showed that self-reported exposure to OOH advertisement was moderately correlated with actual exposure, making this a useful metric for evaluation[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. This study aims to assess if the policy resulted in a change in self-reported exposure to advertisements of HFSS foods and drinks, alcohol, gambling, and consumption or use of these products.\u003c/p\u003e"},{"header":"Material and Methods","content":"\u003cp\u003eThe study protocol was published prior to the start of the analyses, and is available from Open Science Framework (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://osf.io/24cyj\u003c/span\u003e\u003c/span\u003e). The study received ethical approval by the University of Bristol Faculty of Health Sciences Research Ethics Committee (FREC) and was registered with the Open Science Framework. It is reported in accordance with STROBE guidelines (Online Supplementary Material (OSM) Table (T)1).\u003c/p\u003e\n\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n \u003ch2\u003eStudy design\u003c/h2\u003e\n \u003cp\u003eSelf-reported information on exposure to OOH advertising of HFSS products, alcohol and gambling and consumption/use of these products was collected using repeated cross-sectional surveys. The surveys were completed by residents from Bristol (intervention) and the adjacent area of South Gloucestershire (SG) (comparator) before and after the Bristol advertising and sponsorship restrictions policy implementation. In both areas, a similar methodology was used to distribute the pre- and post-policy surveys. In Bristol, the surveys were distributed to approximately 4000 members of the council\u0026rsquo;s Citizen\u0026rsquo;s panel, newsletter subscribers and paper copies were also sent to the most deprived 20% of communities and provided at libraries, in order to capture digitally excluded citizens and other demographic groups. In SG, surveys were distributed to approximately 2,300 members of the council\u0026rsquo;s Viewpoint Panel, as well as paper copies at libraries.\u003c/p\u003e\n \u003cp\u003eThe survey questions and data collection processes have been published previously, and a sample survey can be found within the protocol\u0026rsquo;s appendix (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://osf.io/24cyj\u003c/span\u003e\u003c/span\u003e)[\u003cspan class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e15\u003c/span\u003e].They captured information on whether respondents had: i) been in their local area during the week prior to completing the survey and how much (all week, only a couple of days, away all week), ii) seen advertising for HFSS products, alcohol and gambling in their local area, iii) where they had seen the item advertised (i.e. on a billboard, bus shelter, side of a bus, side of a taxi or elsewhere), and iv) consumption/use of these products. The survey covered key HFSS product categories (biscuits \u0026amp; cakes, sugary cereals, chocolate \u0026amp; sweets, desserts, crisps \u0026amp; savoury snacks, fast-food, and sugary drinks) and included specific questions on types of fast-food chain adverts. The questions all related to exposure/consumption/use during the week prior to questionnaire completion and used multiple choice options. Additional questions asked about frequency of bus use and socio-demographic information. The baseline (pre-policy) survey was conducted between January and March 2022, which was after the policy\u0026rsquo;s inception date (November 2021), but prior to the advertising contracts ending and policy being practically implemented (first week of April 2022). The follow-up (post-policy) survey was conducted in the same period in 2023, after the policy came into effect. After the surveys were completed, the data were collated by Bristol and SG councils and postcodes were translated to Lower Super Output Areas (LSOAs) and anonymised, prior to sending it to the researchers. Respondents were classified as Bristol or SG residents based on their LSOAs, irrespective of which survey they completed. Because of anonymisation we were unable to identify residents who completed both the pre and post implementation surveys. The sample size was powered to detect\u0026thinsp;\u0026gt;\u0026thinsp;5% absolute percentage point reduction in recent consumption of HFSS products, based on data obtained from the 2,560 responses from the baseline survey with 58% reporting consumption of HFSS foods in the previous 7 days.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\n \u003ch2\u003eStatistical analysis\u003c/h2\u003e\n \u003cp\u003eThe data were analysed using Stata version 15.1 (Stata Corporation, College Station, Texas). Index of multiple deprivation (IMD)[\u003cspan class=\"CitationRef\"\u003e23\u003c/span\u003e] was mapped to respondents using their LSOAs[\u003cspan class=\"CitationRef\"\u003e24\u003c/span\u003e]. Differences in the distribution of respondents characteristics (age group, sex, ethnicity, household occupancy, employment status, IMD decile and bus use) between the pre- and post-policy groups within each area were compared using chi-squared tests. The difference in prevalence of self-reported exposure to adverts or consumption/use of unhealthy commodities between pre- and post-policy surveys was calculated for Bristol and SG. The percentage change in exposure to advertisements or consumption/use of unhealthy commodities between pre- and post-policy groups was calculated and assessed using chi-squared tests.\u003c/p\u003e\n \u003cp\u003eA controlled before-after design was used to analyse the average treatment effect on the treated - the estimated change in self-reported exposure to adverts of unhealthy commodities or consumption/use of unhealthy commodities in group of residents in Bristol. Four regression models were used with differing level of adjustments: unadjusted, adjusted for key confounders, additionally adjusted for entropy balancing weights (considered the primary analysis) and additionally adjusted for entropy balancing weights multiplied by population balancing weights. Confounding covariates included; sex (male, female), age (18\u0026ndash;34, 35\u0026ndash;44, 45\u0026ndash;64 and \u0026ge;\u0026thinsp;65 years), ethnicity (white, non-white), household occupancy (single, couple, family, shares and other), IMD (1\u0026ndash;2, 3\u0026ndash;4, 5\u0026ndash;6, 7\u0026ndash;8 and 9\u0026ndash;10), and employment status (full time/part-time and self-employed, unemployed, retired and other). All covariates, except for IMD, had missing data (ranging from 0.6% to 3.1%) which were grouped into a missing category to maintain sample size. Entropy balancing weights[\u003cspan class=\"CitationRef\"\u003e25\u003c/span\u003e] were calculated using the same confounding covariates listed above, such that the primary analysis was a doubly-robust model. A population weight variable was also created so that the gender ratio, age groups and ethnicity in each LSOA in the study population were balanced to match the distribution of these demographics within the source general population of Bristol and SG (calculated using information downloaded from the Office of National Statistics (ONS), 2020 Population Estimates Series).\u003c/p\u003e\n \u003cp\u003eThe regression models included a \u0026lsquo;timepoint\u0026rsquo; variable (pre-policy and post-policy), an area variable (Bristol and SG) and an interaction term (area x timepoint). Main outcome variables were self-reported exposure to any advertisements of HFSS food/drinks, alcohol and gambling and consumption/use of HFSS foods/drinks, alcohol and gambling. Exposure to payday loans adverts was originally an outcome but since there were no adverts in this category either before or after the policy (ref pre-print paper), this outcome was dropped. The secondary outcome variables included the specific subcategories within these groups and where respondents saw the adverts. All outcomes were binary variables (yes/no) except for amount spent on gambling (categorical; \u0026pound;0-\u0026pound;10, \u0026gt;\u0026pound;10-\u0026pound;50, \u0026gt;\u0026pound;50-\u0026pound;100, \u0026gt;\u0026pound;100) and for frequency of consumption of HFSS foods and drinks (0, 1\u0026ndash;3, 4\u0026ndash;6 and 7 days a week). Regression beta-coefficients and 95% confidence intervals were converted to percentage point changes in exposure/consumption for ease of interpretation.\u003c/p\u003e\n\u003c/div\u003e\n\u003ch3\u003eSensitivity Analyses\u003c/h3\u003e\n\u003cp\u003eSubgroup analyses were undertaken to explore potential differences in the \u0026lsquo;treatment effect\u0026rsquo; by sex, age-group, ethnicity, IMD, bus use, amount of time in local area in the week before the survey and frequency of visits to the city centre. Finally, the main models were repeated while excluding; i) respondents who reported having only been in the local area for a couple of days in the past week, and ii) respondents with the highest and lowest IMD deciles; the latter because of significant differences in the distribution of IMD between the samples from the intervention and control groups at either end of the IMD range (Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eThe final study sample, after exclusions, included 4,619 respondents, with 2,543 respondents from the pre-policy survey (n=1,110 from Bristol and n=1,433 from SG), and 2,076 respondents from the post-policy survey (n=711 from Bristol and n=1,365 from SG), (Figure 1). The majority of respondents were over 45 years old, of white ethnicity and female (Table 1). Compared to SG, respondents in Bristol were younger, more likely to live in deprived areas and were more likely to be in full time employment.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe results across both areas showed that during the week prior to completing the survey, 58.2% of respondents reported seeing adverts of any unhealthy commodity and 39.7% reported seeing adverts for HFSS products (OSM T2). Self-reported exposure to advertising of any unhealthy commodity advert was higher in Bristol compared to SG; 66.0% and 66.5% in Bristol vs 52.2% and 53.9% in SG in pre- and post-policy survey responses, respectively (Figure 2A; OSM T2 \u0026amp; T3). In both pre-policy and post-policy surveys respectively, a higher proportion of respondents in Bristol compared to SG reported seeing adverts for any HFSS food/drink (52.6% and 50.5% in Bristol vs 31.0% and 32.8% in SG), with a similar pattern seen for HFSS food/drinks specifically marketed at children, fast-food chains, alcoholic drinks, and gambling companies). In contrast, a higher proportion of respondents in SG compared to Bristol reported seeing adverts for establishments serving alcohol (Figure 2A; OSM T2 \u0026amp; T3). For all the abovementioned exposures there was generally minimal changes between pre- and post-policy responses within each area.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eWithin the HFSS food/drinks advert groups, fast-food adverts were most commonly reported across both areas (33.1%), followed by sugary drinks (14.8%) and chocolate and sweets (14.5%), with a higher exposure reported in Bristol compared to SG in both pre- and post-policy surveys (Figure 2B; OSM T2 \u0026amp; T3). In contrast, self-reported consumption of any HFSS foods/drink was higher in SG than Bristol (93.0% and 93.8% in SG vs 87.5% and 86.8% in Bristol, pre-policy and post-policy survey respectively),(Figure 2C; OSM T4 \u0026amp; T5). In Bristol, reported alcohol consumption was generally lower in the post-policy compared to pre-policy survey, but consumption of HFSS products and gambling activity were generally comparable (Figure 2E and 2D, OSM T4 \u0026amp; T5). The most common places respondents reported seeing the unhealthy commodity adverts were on billboards, bus shelters and sides of buses (Figure 3). In Bristol, the proportion of HFSS products, gambling and alcohol adverts seen on bus shelters was significantly lower after the policy compared to before, while this pattern was not evident in SG (Figure 4, OSM T6). \u0026nbsp; \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFollowing the implementation of the policy, there was barely any change in self-reported exposure to adverts of any unhealthy commodity in the doubly robust model; -6.9% (95% CI -34.9, 35.0) percentage point reduction compared to comparator group (Table 2). There was also no evidence of changes in reported exposure to the different categories of unhealthy commodity adverts; percentage point change in reported exposure was -19.2% (95% CI -45.1,17.4) for HFSS foods/drink adverts, 33.6% (95% CI -14.8, 100.0) for alcoholic drinks adverts and -8.6% (95% CI -38.1, 36.3) for gambling adverts (Table 2). For HFSS product subgroups, the majority of the point estimates were negative, representing a reduction in reported exposure, albeit non-significant (Table 3). There were generally minimal differences between the estimates derived from crude and doubly robust models for the main unhealthy commodity advert groups (Table 2), or when models were additionally adjusted for population weighting (OSM T7-T9). Although there were reductions following the policy in any gambling activity (-17.3% (95% CI -45.7, 25.9), consumption of any HFSS product (-2.0% (95% CI -49.3, 89.6) and most HFSS product subgroups, in Bristol compared to comparators, none of these reached statistical significance (Table 3 and OSM T9).\u003c/p\u003e\n\u003cp\u003eIn secondary analyses, repeating the main models stratified by respondents\u0026rsquo; characteristics, there was no evidence of changes in reported exposure any advert of unhealthy commodities or consumption of unhealthy commodities within different respondent subgroups (Table 4). In analyses stratified by location of observed adverts, there was no evidence of a change in reported exposure to adverts of HFSS products seen at bus shelters or other advertising sites (data not tabulated). In sensitivity analyses excluding respondents in the top and bottom IMD from the analysis, the change in reported exposure to any unhealthy commodity advert (\u0026beta; -0.5 (95% CI -1.1, 0.1) and consumption of any HFSS food/drink (\u0026beta; -0.2 (95% CI -1.1, 0.7) in Bristol compared to the comparator group was comparable to the analysis of the full sample (data not tabulated).\u0026nbsp;\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study aimed to evaluate the perceived change in advertising of unhealthy foods/drinks, alcohol and gambling, as well as any change in consumption or use of these commodities, after the implementation of a new advertisement restriction policy in Bristol in 2022. The findings indicate little evidence of changes in self-reported exposure to advertisements of unhealthy commodities in Bristol, or changes in consumption of HFSS products and alcohol or participation in gambling, following implementation of the policy. However, it is noteworthy that for HFSS products (exposure and consumption), the observed changes following the policy implementation were in the hypothesised direction.\u003c/p\u003e\u003cp\u003eThere are several potential explanations for these findings. Firstly, the study may have been underpowered, particularly because the post-policy survey group in Bristol (the exposed arm) had approximately half the number of respondents than the pre- and post-policy comparator group, which was due to lower participation rates. In addition, although entropy weights were used to balance out the socio-demographic differences between respondents in Bristol and SG (particularly IMD levels between the areas), residual confounding cannot be ruled out. Another explanation is that the advertising restrictions only affected a relatively small proportion of total OOH advertisement space within Bristol, because the policy only applied to council-owned advertising spaces (283 bus shelters). In line with this residents reported seeing advertisements of unhealthy commodities (including HFSS products) on many other OOH spaces which were not subject to the policy because they were commercially owned (i.e. billboards and buses). In addition, our previous research showed that before the policy was implemented only 11% of bus shelter advertisements in Bristol displayed non-compliant unhealthy commodities (ref pre-print paper), indicating the baseline level of exposure to unhealthy advertising on bus shelters was already low. This may have been further compounded by the knock-on effects of the Covid-19 pandemic, which resulted in reductions in transport use due to more people working from home[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eCollectively, these factors suggest that any change in exposure to OOH advertising of unhealthy commodities as a result of the policy may have been too small (relative to the total OOH advertising environment) to lead to noticeable and measurable changes. Our findings also align with another arm of the BEAR study evaluating changes in household purchasing data, which found no evidence of a change in household purchasing of HFSS products in Bristol following the policy (ref pre-print paper).\u003c/p\u003e\u003cp\u003eTo the best of our knowledge, there are no directly comparable studies assessing changes in perceived exposure to OOH unhealthy commodity advertising following advertising restriction policies. However, we can compare our results on overall exposure to unhealthy commodity advertising to other research on OOH advertising exposure. For instance, our findings on self-reported exposure to HFSS products were similar to that observed in the TfL evaluation[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], with 36% of participants reporting to have seen HFSS advertising on transport networks in the past week in London, which is comparable to 39% in our study (for Bristol and SG). Respondents in London with a lower socioeconomic position were more likely to report seeing OOH advertisements of unhealthy foods/drinks[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. In the pre-policy baseline data from our study respondents from more deprived areas, compared to less deprived areas, also observed more unhealthy commodity advertising, particularly for HFSS products[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. It would be logical to hypothesise that this group of respondents could be more likely to notice changes in advertising resulting from the policy, due to greater overall exposure, however in stratified analyses by area-level deprivation there was no evidence of this. Likewise, there was no evidence of a reduction in exposure to unhealthy commodity adverts for respondents who used buses regularly (daily or several times a week).\u003c/p\u003e\u003cp\u003eThe strengths of the study include the relatively large sample size, which despite having a smaller number of responses than expected in Bristol after the implementation of the policy, still included over 4,500 respondents from Bristol and the comparator area. In addition, specific strategies were used to try and include harder-to-reach individuals, for example, by providing paper copies and distributing surveys via libraries. Since the demographic profile of the surveyed residents in Bristol and SG were not directly comparable to the general population (the surveyed sample had a higher percentage of women and older people), we used a population weighting variable in an additional analysis to balance these demographics to the general population. However, there were minimal changes in the results even after adjusting for population weighting. Another strength is that we were able to explore if the results differed for the subgroup of respondents who were in the area the entire week and those who specifically used public transport (these showed similar findings to the main analysis).\u003c/p\u003e\u003cp\u003eThe study has several limitations, firstly advertising exposure was based on self-reported information and so would be susceptible to measurement error[\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. A related limitation is that information on consumption of HFSS products and alcohol was based on recalling which types of HFSS products and alcoholic drinks had been consumed in the past week and over how many days. This data is also likely to be subject to measurement error, including recall and social desirability bias. We aimed to reduce this source of measurement error by only asking about exposure and consumption in the past week. This may mean that the reported exposure and consumption was not representative of habitual exposure and consumption. Furthermore, some respondents will have travelled outside of their immediate neighbourhood during the past week, so when asked about what adverts they have seen in their local area (their street and surrounding streets), it is possible that some respondents may have unintentionally reported adverts they saw in other areas.\u003c/p\u003e\u003cp\u003eThere were also socio-demographic differences between respondents from Bristol and SG, with more respondents from Bristol having a lower IMD and being in full time employment. In part this may have resulted from differences in the sampling strategies in both areas. However, entropy balancing weights were used in the regression models, and sensitivity analyses excluded the extreme IMDs to try and address these differences. A further limitation is that we did not capture information on intensity of exposure to unhealthy commodity adverts before and after the policy, as the survey questions focused on whether residents had seen \u003cem\u003eany\u003c/em\u003e advertising of HFSS products in their local area, classifying participants as exposed or not. This was a deliberate choice as asking residents how many adverts of unhealthy commodities they had seen in the past week would have likely introduced additional measurement error. Therefore, although there was no evidence of a reduction in seeing any HFSS product adverts following the policy, there could have been a reduction in the number of HFSS products adverts observed (intervention dose) which was not captured. Indeed, the in-person audit of actual advertising displayed on bus shelters in Bristol before and after the policy\u0026rsquo;s implementation showed there was a substantial reduction in number of adverts of unhealthy commodities, falling from 11% of all advertising before to 0.8% after the policy, mainly due to a reduction in adverts for HFSS products (ref pre-print paper). Regardless, when we assessed the change in self-reported exposure to adverts of HFSS products specifically seen at bus shelters, there was still no evidence of a reduction in exposure following the policy. However, it should be noted that in baseline research within the BEAR study there was a significant association between measured exposure of HFSS product adverts (through in-person audits) and self-reported exposure, particularly for exposure at bus shelters (reporting ratio (RR) of 1.68; 95% CI 1.40 to 2.03)[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Finally, we could not calculate the response rates as we didn\u0026rsquo;t have information on how many people saw the surveys in libraries for example, or when they stopped being available.\u003c/p\u003e\u003cp\u003eDespite finding no clear evidence of changes in self-reported exposure to adverts of unhealthy commodities, the policy aligns with the council\u0026rsquo;s \u0026lsquo;health in all policies\u0026rsquo; initiative. This supports their drive to deliver clear and consistent messaging regarding public health issues with the overarching aim to improve the health of all residents, as reported in the qualitative evaluation of the policy implementation (ref pre-print paper). As additional regions across the UK implement similar policies the number of OOH unhealthy product adverts that people see should progressively decline[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. However, OOH advertising only contributes to a relatively minor portion of where people see unhealthy commodity advertising, with advertising on online platforms becoming increasingly prevalent[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Research indicates that advertising restrictions which target a wide range of settings are more likely to have a greater impact, partly because companies can adapt to partial bans by refocusing advertising to non-restricted media to reach their target audience[\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. This is particularly relevant when tackling childhood obesity, because of concerns that children are more susceptible to the persuasive intent of food marketing[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e], which often promote energy-dense, nutrient-poor products[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. Indeed, in the UK, a third of food and soft drink advertising expenditure is for marketing confectionery, snacks, desserts and soft drinks compared to only 1% for fruit and vegetables[\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]. Evidence also suggests that nation-wide mandatory regulations are likely to be more effective than voluntary policies[\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. Therefore, policies which restrict advertising of unhealthy commodities, including OOH settings, can been seen as part of a series of strategies to address the CDoH and their negative impact on NCDs and quality of life[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eIn conclusion, our findings suggest that following implementation of a new advertisement and sponsorship policy restricting advertisement of unhealthy commodities on Council-owned spaces in Bristol, there was no measurable significant change in residents reporting being exposed to OOH advertising of unhealthy commodities, nor evidence of significant changes in self-reported consumption of HFSS products, alcohol or participating in gambling. Future advertising restriction policies may need to be extended to cover more outdoor spaces and a wider variety of advertising platforms in order to sufficiently reduce unhealthy commodity advertising that people notice. However, the optimal intervention dose is still unknown and warrants further research, along with the potential impact this could have on population health and healthcare cost savings.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cspan\u003eThe participants consented to participate in the study.\u0026quot;\u003c/span\u003e\u003c/p\u003e\u003ch2\u003eFunding:\u003c/h2\u003e\n\u003cp\u003eThis project is funded by the National Institute for Health and Care Research [Public Health Research Programme \u0026ndash; project 152114]. LJS, CSR, RB, SH and GB and JH are funded by the National Institute for Health and Care Research Applied Research Collaboration West (NIHR ARC West). FDV, RJ and WH are partly funded by NIHR ARC West. The views and opinions expressed herein are those of the authors and do not necessarily reflect those of the NIHR PHR Programme, NIHR or the Department of Health and Social Care. Funders had no involvement in data analysis, data interpretation or writing of the paper.\u003c/p\u003e\n\u003ch2\u003eAcknowledgements:\u003c/h2\u003e\n\u003cp\u003eThe authors would like to thank Bristol City Council and South Gloucestershire Council for their support in the design and implementation of the BEAR study, as well as Bristol, North Somerset and South Gloucestershire NHS Integrated Care Board. We would also like to thank all the members of the Study Oversight Group. Finally, we would like to thank all the participants from Bristol and South Gloucestershire who filled out the resident surveys.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eLi J, Pandian V, Davidson PM, Song Y, Chen N, Fong DYT: \u003cstrong\u003eBurden and attributable risk factors of non-communicable diseases and subtypes in 204 countries and territories, 1990-2021: a systematic analysis for the global burden of disease study 2021\u003c/strong\u003e. \u003cem\u003eInt J Surg \u003c/em\u003e2025, \u003cstrong\u003e111\u003c/strong\u003e(3):2385-2397.\u003c/li\u003e\n\u003cli\u003eKickbusch I, Allen L, Franz C: \u003cstrong\u003eThe commercial determinants of health\u003c/strong\u003e. \u003cem\u003eLancet Glob Health \u003c/em\u003e2016, \u003cstrong\u003e4\u003c/strong\u003e(12):e895-e896.\u003c/li\u003e\n\u003cli\u003eGoyder E, Blank L, Baxter S, van Schalkwyk MC: \u003cstrong\u003eTackling gambling related harms as a public health issue\u003c/strong\u003e. \u003cem\u003eLancet Public Health \u003c/em\u003e2020, \u003cstrong\u003e5\u003c/strong\u003e(1):e14-e15.\u003c/li\u003e\n\u003cli\u003eGiesbrecht N, Reisdorfer E, Shield K: \u003cstrong\u003eThe impacts of alcohol marketing and advertising, and the alcohol industry\u0026apos;s views on marketing regulations: Systematic reviews of systematic reviews\u003c/strong\u003e. \u003cem\u003eDrug Alcohol Rev \u003c/em\u003e2024, \u003cstrong\u003e43\u003c/strong\u003e(6):1402-1425.\u003c/li\u003e\n\u003cli\u003eWHO: \u003cstrong\u003eWorld Health Organisation. 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Taking down junk food ads. 2019. \u003c/strong\u003e[.https://www.sustainweb.org/publications/taking_down_junk_food_ads/]\u003c/li\u003e\n\u003cli\u003eAlfraidi A, Alafif N, Alsukait R: \u003cstrong\u003eThe Impact of Mandatory Food-Marketing Regulations on Purchase and Exposure: A Narrative Review\u003c/strong\u003e. \u003cem\u003eChildren (Basel) \u003c/em\u003e2023, \u003cstrong\u003e10\u003c/strong\u003e(8):1277-1288.\u003c/li\u003e\n\u003cli\u003eKovic Y, Noel JK, Ungemack JA, Burleson JA: \u003cstrong\u003eThe impact of junk food marketing regulations on food sales: an ecological study\u003c/strong\u003e. \u003cem\u003eObes Rev \u003c/em\u003e2018, \u003cstrong\u003e19\u003c/strong\u003e(6):761-769.\u003c/li\u003e\n\u003cli\u003eNorman J, Kelly B, Boyland E, McMahon A-T: \u003cstrong\u003eThe Impact of Marketing and Advertising on Food Behaviours: Evaluating the Evidence for a Causal Relationship\u003c/strong\u003e. \u003cem\u003eCurrent Nutrition Reports \u003c/em\u003e2016, \u003cstrong\u003e5\u003c/strong\u003e(3):139-149.\u003c/li\u003e\n\u003cli\u003eDhar T, Baylis K: \u003cstrong\u003eFast-Food Consumption and the Ban on advertising targeting children_the quebec experience.\u003c/strong\u003e \u003cem\u003eJournal of Marketing Research \u003c/em\u003e2011, \u003cstrong\u003e48\u003c/strong\u003e:799\u0026ndash;813.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eThe Food Foundation. The Broken Plate. London 2023. \u003c/strong\u003e[https://foodfoundation.org.uk/sites/default/files/2023-10/TFF_The%20Broken%20Plate%202023_Digital_FINAL..pdf]\u003c/li\u003e\n\u003cli\u003ePopkin BM, Adair LS, Ng SW: \u003cstrong\u003eGlobal nutrition transition and the pandemic of obesity in developing countries\u003c/strong\u003e. \u003cem\u003eNutr Rev \u003c/em\u003e2012, \u003cstrong\u003e70\u003c/strong\u003e(1):3-21.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTables 1 to 4 are available in the Supplementary Files section.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[{"identity":"66744481-a11e-4d93-af36-b9673a4fafb5","identifier":"10.13039/501100000272","name":"National Institute for Health Research","awardNumber":"152114","order_by":0}],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"Bristol, North Somerset and South Gloucestershire","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Advertising, HFSS, Public Health, Policy Evaluation, Commercial determinants of health","lastPublishedDoi":"10.21203/rs.3.rs-7600850/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7600850/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e\u003cp\u003ePolicies restricting advertisements of high fat, salt and sugar (HFSS) products and other unhealthy commodities are potentially effective tools to improve diet, reduce diet-related diseases and address public health inequalities. Bristol was the first UK city outside London to introduce such a policy on council-owned advertisement spaces in 2021. This study evaluates the policy\u0026rsquo;s impact on self-reported exposure to advertisements of HFSS products, alcohol and gambling, and self-reported consumption or use of these products.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003eA repeated cross-sectional survey of Bristol residents (intervention) and neighbouring South Gloucestershire residents (comparator) was administered before (n\u0026thinsp;=\u0026thinsp;2,543) and after (n\u0026thinsp;=\u0026thinsp;2,076) the policy was implemented. Self-reported exposure to outdoor adverts on HFSS products, alcohol and gambling in the local area and consumption or use of these products was collected, along with socio-demographic information. The intervention effect was analysed using a weighted controlled before-after design.\u003c/p\u003e\u003ch2\u003eResult\u003c/h2\u003e\u003cp\u003eFollowing the policy, there was no evidence of a change in self-reported exposure to advertising of unhealthy commodities, compared to the comparator group; percentage point change in exposure to advertising was \u0026minus;\u0026thinsp;6.9% (95% CI -34.9, 35.0) for any unhealthy commodity, -19.2% (95% CI -45.1, 17.4) for HFSS foods/drinks, 33.6% (95% CI -14.8, 100) for alcoholic drinks and \u0026minus;\u0026thinsp;8.6% (95% CI -38.1, 36.3) for gambling. Likewise, there were non-significant changes in self-reported consumption of HFSS products (-2.0% (95% CI -49.3, 89.6), alcohol (15.0% (95% CI -18.9, 64.9) and participation in gambling (-17.3% (95% CI -45.7, 25.9) following the introduction of the policy in Bristol, compared to comparators.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e\u003cp\u003eFollowing the implementation of the policy there was no measurable reduction in self-reported exposure to outdoor advertising of unhealthy commodities, nor was there much evidence of changes in reported consumption of HFSS products, alcohol or gambling. This may be attributable to the relatively small Council-owned outdoor advertisement estate (~\u0026thinsp;30%), so changes in exposure may have been too small to lead to noticeable effects. However, this policy aligns with Bristol City Council\u0026rsquo;s \u0026lsquo;Health in all Policies\u0026rsquo; approach aimed to support a systems-wide approach to improve health.\u003c/p\u003e","manuscriptTitle":"Evaluation of the impact of the Bristol’s outdoor advertisement restrictions policy on self-reported exposure to advertisements, consumption and use of unhealthy commodities.","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-16 14:18:01","doi":"10.21203/rs.3.rs-7600850/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"f929609c-0955-41db-95be-6e07e430f771","owner":[],"postedDate":"September 16th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-09-16T14:18:01+00:00","versionOfRecord":[],"versionCreatedAt":"2025-09-16 14:18:01","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7600850","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7600850","identity":"rs-7600850","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}