Impact of the UK soft drinks industry levy on health and health inequalities in children and adolescents in England: An interrupted time series analysis and population health modelling study.

BACKGROUND: The soft drinks industry levy (SDIL) in the United Kingdom has led to a significant reduction in household purchasing of sugar in drinks. In this study, we examined the potential medium- and long-term implications for health and health inequalities among children and adolescents in England. METHODS AND FINDINGS: We conducted a controlled interrupted time series analysis to measure the effects of the SDIL on the amount of sugar per household per week from soft drinks purchased, 19 months post implementation and by index of multiple deprivation (IMD) quintile in England. We modelled the effect of observed sugar reduction on body mass index (BMI), dental caries, and quality-adjusted life years (QALYs) in children and adolescents (0 to 17 years) by IMD quintile over the first 10 years following announcement (March 2016) and implementation (April 2018) of the SDIL. Using a lifetable model, we simulated the potential long-term impact of these changes on life expectancy for the current birth cohort and, using regression models with results from the IMD-specific lifetable models, we calculated the impact of the SDIL on the slope index of inequality (SII) in life expectancy. The SDIL was found to have reduced sugar from purchased drinks in England by 15 g/household/week (95% confidence interval: -10.3 to -19.7). The model predicts these reductions in sugar will lead to 3,600 (95% uncertainty interval: 946 to 6,330) fewer dental caries and 64,100 (54,400 to 73,400) fewer children and adolescents classified as overweight or obese, in the first 10 years after implementation. The changes in sugar purchasing and predicted impacts on health are largest for children and adolescents in the most deprived areas (Q1: 11,000 QALYs [8,370 to 14,100] and Q2: 7,760 QALYs [5,730 to 9,970]), while children and adolescents in less deprived areas will likely experience much smaller simulated effects (Q3: -1,830 QALYs [-3,260 to -501], Q4: 652 QALYs [-336 to 1,680], Q5: 1,860 QALYs [929 to 2,890]). If the simulated effects of the SDIL are sustained over the life course, it is predicted there will be a small but significant reduction in slope index of inequality: 0.76% (95% uncertainty interval: -0.9 to -0.62) for females and 0.94% (-1.1 to -0.76) for males. CONCLUSIONS: We predict that the SDIL will lead to medium-term reductions in dental caries and overweight/obesity, and long-term improvements in life expectancy, with the greatest benefits projected for children and adolescents from more deprived areas. This study provides evidence that the SDIL could narrow health inequalities for children and adolescents in England.

Parliamentary reaction to the announcement and implementation of the UK Soft Drinks Industry Levy: applied thematic analysis of 2016-2020 parliamentary debates.

OBJECTIVE: The UK Soft Drinks Industry Levy (SDIL) (announced in March 2016; implemented in April 2018) aims to incentivise reformulation of soft drinks to reduce added sugar levels. The SDIL has been applauded as a policy success, and it has survived calls from parliamentarians for it to be repealed. We aimed to explore parliamentary reaction to the SDIL following its announcement until two years post-implementation in order to understand how health policy can become established and resilient to opposition. DESIGN: Searches of Hansard for parliamentary debate transcripts that discussed the SDIL retrieved 186 transcripts, with 160 included after screening. Five stages of Applied Thematic Analysis were conducted: familiarisation and creation of initial codebooks; independent second coding; codebook finalisation through team consensus; final coding of the dataset to the complete codebook; and theme finalisation through team consensus. SETTING: The United Kingdom Parliament. PARTICIPANTS: N/A. RESULTS: Between the announcement (16/03/2016) - royal assent (26/04/2017), two themes were identified 1: SDIL welcomed cross-party 2: SDIL a good start but not enough. Between royal assent - implementation (5/04/2018), one theme was identified 3: The SDIL worked - what next? The final theme identified from implementation until 16/03/2020 was 4: Moving on from the SDIL. CONCLUSIONS: After the announcement, the SDIL had cross-party support and was recognised to have encouraged reformulation prior to implementation. Lessons for governments indicate that the combination of cross-party support and a policy's documented success in achieving its aim can help cement the resilience of it to opposition and threats of repeal.

The impact of the COVID-19 pandemic on cardiovascular disease prevention and corresponding geographical inequalities in England: interrupted time series analysis.

BACKGROUND: There has been disruption to the detection and management of those with hypertension and atrial fibrillation (AF) during the COVID-19 pandemic. This is likely to vary geographically and could have implications for future mortality and morbidity. We aimed to estimate the change in diagnosed prevalence, treatment and prescription indicators for AF and hypertension and assess corresponding geographical inequalities. METHODS: Using the Quality and Outcomes Framework (2016/17 to 2021/22) and the English Prescribing Datasets (2018 to 2022), we described age standardised prevalence, treatment and prescription item rates for hypertension and AF by geography and over time. Using an interrupted time-series (ITS) analysis, we estimated the impact of the pandemic (from April 2020) on missed diagnoses and on the percentage change in medicines prescribed for these conditions. Finally, we described changes in treatment indicators against Public Health England 2029 cardiovascular risk targets. RESULTS: We observed 143,822 fewer (-143,822, 95%CI:-226,144, -61,500, p = 0.001) diagnoses of hypertension, 60,330 fewer (-60,330, 95%CI: -83,216, -37,444, p = 0.001) diagnoses of AF and 1.79% fewer (-1.79%, 95%CI: -2.37%, -1.22%), p < 0.0001) prescriptions for these conditions over the COVID-19 impact period. There was substantial variation across geography in England in terms of the indirect impact of the COVID-19 pandemic on the diagnosis, prescription, and treatment rates of hypertension and AF. 20% of Sub Integrated Care Boards account for approximately 62% of all missed diagnoses of hypertension. The percentage of individuals who had their hypertension controlled fell from 75.8% in 2019/20 to 64.1% in 2021/22 and the percentage of individuals with AF who were risk assessed fell from 97.2% to 90.7%. CONCLUSIONS: Hypertension and AF detection and management were disrupted during the COVID-19 pandemic. The disruption varied considerably across diseases and geography. This highlights the utility of administrative and geographically granular datasets to inform targeted efforts to mitigate the indirect impacts of the pandemic through applied secondary prevention measures.

Changes in soft drinks purchased by British households associated with the UK soft drinks industry levy: a controlled interrupted time series analysis.

OBJECTIVE: To determine changes in household purchases of drinks 1 year after implementation of the UK soft drinks industry levy (SDIL). DESIGN: Controlled interrupted time series. PARTICIPANTS: Households reporting their purchasing to a market research company (average weekly n=22 091), March 2014 to March 2019. INTERVENTION: A two-tiered tax levied on soft drinks manufacturers, announced in March 2016 and implemented in April 2018. Drinks with ≥8 g sugar/100 mL (high tier) are taxed at £0.24/L, drinks with ≥5 to <8 g sugar/100 mL (low tier) are taxed at £0.18/L. MAIN OUTCOME MEASURES: Absolute and relative differences in the volume of, and amount of sugar in, soft drinks categories, all soft drinks combined, alcohol and confectionery purchased per household per week 1 year after implementation. RESULTS: In March 2019, compared with the counterfactual, purchased volume of high tier drinks decreased by 140.8 mL (95% CI 104.3 to 177.3 mL) per household per week, equivalent to 37.8% (28.0% to 47.6%), and sugar purchased in these drinks decreased by 16.2 g (13.5 to 18.8 g), or 42.6% (35.6% to 49.6%). Purchases of low tier drinks decreased by 170.5 mL (154.5 to 186.5 mL) or 85.8% (77.8% to 93.9%), with an 11.5 g (9.1 to 13.9 g) reduction in sugar in these drinks, equivalent to 87.8% (69.2% to 106.4%). When all soft drinks were combined irrespective of levy tier or eligibility, the volume of drinks purchased increased by 188.8 mL (30.7 to 346.9 mL) per household per week, or 2.6% (0.4% to 4.7%), but sugar decreased by 8.0 g (2.4 to 13.6 g), or 2.7% (0.8% to 4.5%). Purchases of confectionery and alcoholic drinks did not increase. CONCLUSIONS: Compared with trends before the SDIL was announced, 1 year after implementation, volume of all soft drinks purchased combined increased by 189 mL, or 2.6% per household per week. The amount of sugar in those drinks was 8 g, or 2.7%, lower per household per week. Further studies should determine whether and how apparently small effect sizes translate into health outcomes. TRIAL REGISTRATION NUMBER: ISRCTN18042742.

Explaining differential socioeconomic effects in population health interventions: development and application of a new tool to classify intervention agentic demand.

BACKGROUND: The agentic demand of population health interventions (PHIs) might influence how interventions work. Highly agentic interventions (eg, information campaigns) rely on recipients noticing and responding to the intervention. Resources required for individuals to benefit from highly agentic interventions have a socioeconomical pattern, thus agentic demand might affect intervention effectiveness and equity. Systematic evidence exploring these associations is missing due to the absence of adequate tools to classify agentic demands. We aimed to develop such a tool and test its application. METHODS: Our iterative development process involved: (1) systematic identification of diet and physical activity PHIs; (2) coding of intervention actors and actions; (3) data synthesis; (4) expert qualitative feedback; and (5) reliability assessment. We searched nine databases for articles published between Jan 1, 2010, and Aug 17, 2020. For all included articles, we coded the actors (people required to act within an intervention) and their actions (what they were required to do for the intervention to have its intended effects). We combined these codes for similar intervention types to develop overarching schematic flow chart diagrams used to identify concepts, and we organised these into a draft tool. After expert feedback, and we assessed inter-rater reliability of the final version. We applied the final tool in a proof-of-concept review, extracting studies from three existing equity-focused systematic reviews on tool category, overall intervention effect, and differential socioeconomic effects and visualised findings. FINDINGS: We identified three concepts affecting agentic demands of intervention components: exposure, two levels (how recipients encounter the intervention); mechanism of action, five levels; and engagement, two levels (how recipients respond to the intervention). We then combined these concepts to form 20 categories that grouped together interventions with similar agentic demands. In the review, we applied the tool to 26 PHIs that included 163 components. Intervention components were concentrated in a small number of categories, and their categorisation was related to intervention equity but not to effectiveness. INTERPRETATION: We present a novel tool to classify the agentic demand of PHIs and demonstrate its feasibility within a systematic review. Linking intervention types to their effect on inequalities enables these factors to be considered when designing or selecting interventions. Users of the tool can avoid implementing intervention types that are likely to widen inequalities or implement them alongside counter-strategies to minimise any adverse equity effects. Applying this tool within future research, policy, and practice to design, select, evaluate, and synthesise evidence from PHIs has the potential to advance our understanding of how interventions work and their effect on socioeconomic inequalities. FUNDING: Public Health Policy Research Unit (PH-PRU), National Institute for Health and Care Research (NIHR) Policy Research Programme.

A systematic scoping review evaluating sugar-sweetened beverage taxation from a systems perspective.

Systems thinking can reveal surprising, counterintuitive or unintended reactions to population health interventions (PHIs), yet this lens has rarely been applied to sugar-sweetened beverage (SSB) taxation. Using a systematic scoping review approach, we identified 329 papers concerning SSB taxation, of which 45 considered influences and impacts of SSB taxation jointly, involving methodological approaches that may prove promising for operationalizing a systems informed approach to PHI evaluation. Influences and impacts concerning SSB taxation may be cyclically linked, and studies that consider both enable us to identify implications beyond a predicted linear effect. Only three studies explicitly used systems thinking informed methods. Finally, we developed an illustrative, feedback-oriented conceptual framework, emphasizing the processes that could result in an SSB tax being increased, maintained, eroded or repealed over time. Such a framework could be used to synthesize evidence from non-systems informed evaluations, leading to novel research questions and further policy development.

Understanding the role of the state in dietary public health policymaking: a critical scoping review.

Despite evidence that dietary population health interventions are effective and widely accepted, they remain the topic of intense debate centring on the appropriate role of the state. This review sought to identify how the role of the state in intervening in individuals' food practices is conceptualized across a wide range of literatures. We searched 10 databases and 4 journals for texts that debated dietary population health interventions designed to affect individuals' health-affecting food practices. Two co-authors independently screened these texts for eligibility relative to inclusion and exclusion criteria. Thirty-five texts formed our final corpus. Through critical reflexive thematic analysis (TA), we generated 6 themes and 2 subthemes concerning choice, responsibility for health, balancing benefits and burdens of intervention, the use of evidence, fairness, and the legitimacy of the state's actions. Our analysis found that narratives that aim to prevent effective regulation are entrenched in academic literatures. Discourses that emphasized liberty and personal responsibility framed poor health as the result of 'lifestyle choices'. Utilitarian, cost-benefit rationales pervaded arguments about how to best balance the benefits and burdens of state intervention. Claims about fairness and freedom were used to evoke powerful common meanings, and evidence was used politically to bolster interests, particularly those of the food industry. This review identifies and critically analyses key arguments for and against population dietary public health policies. Our findings should motivate public health researchers and practitioners to avoid unreflexively embracing framings that draw on the languages and logics of free market economics.

Industry views of the UK Soft Drinks Industry Levy: a thematic analysis of elite interviews with food and drink industry professionals, 2018-2020.

OBJECTIVES: The UK Soft Drinks Industry Levy (SDIL), implemented in 2018, has been successful in reducing the sugar content and purchasing of soft drinks, with limited financial impact on industry. Understanding the views of food and drink industry professionals involved in reacting to the SDIL is important for policymaking. However, their perceptions of the challenges of implementation and strategic responses are unknown. The aim of this study, therefore, was to explore how senior food and drink industry professionals viewed the SDIL. DESIGN: We undertook a qualitative descriptive study using elite interviews. Data were analysed using Braun and Clarke's thematic analysis, taking an inductive exploratory and descriptive approach not informed by prior theory or frameworks. SETTING AND PARTICIPANTS: Interviews were conducted via telephone with 14 senior professionals working in the food and drink industry. RESULTS: Five main themes were identified: (1) a level playing field…for some; industry accepted the SDIL as an attempt to create a level playing field but due to the exclusion of milk-based drinks, this was viewed as inadequate, (2) complex to implement, but no lasting negative effects; the SDIL was complex, expensive and time consuming to implement, with industry responses dependent on leadership buy-in, (3) why us?-the SDIL unfairly targets the drinks industry; soft drinks are an unfair target when other categories also contain high sugar, (4) the consumer is king; consumers were a key focus of the industry response to this policy and (5) the future of the SDIL; there appeared to be a wider ripple effect, which primed industry to prepare for future regulation in support of health and environmental sustainability. CONCLUSIONS: Insights from senior food and drink industry professionals illustrate how sugar-sweetened beverage taxes might be successfully implemented and improve understanding of industry responses to taxes and other food and drink policies. TRIAL REGISTRATION NUMBER: ISRCTN18042742.

Socioeconomic inequalities of Long COVID: a retrospective population-based cohort study in the United Kingdom.

OBJECTIVES: To estimate the risk of Long COVID by socioeconomic deprivation and to further examine the inequality by sex and occupation. DESIGN: We conducted a retrospective population-based cohort study using data from the ONS COVID-19 Infection Survey between 26 April 2020 and 31 January 2022. This is the largest nationally representative survey of COVID-19 in the UK with longitudinal data on occupation, COVID-19 exposure and Long COVID. SETTING: Community-based survey in the UK. PARTICIPANTS: A total of 201,799 participants aged 16 to 64 years and with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. MAIN OUTCOME MEASURES: The risk of Long COVID at least 4 weeks after SARS-CoV-2 infection by index of multiple deprivation (IMD) and the modifying effects of socioeconomic deprivation by sex and occupation. RESULTS: Nearly 10% (n = 19,315) of participants reported having Long COVID. Multivariable logistic regression models, adjusted for a range of variables (demographic, co-morbidity and time), showed that participants in the most deprived decile had a higher risk of Long COVID (11.4% vs. 8.2%; adjusted odds ratio (aOR): 1.46; 95% confidence interval (CI): 1.34, 1.59) compared to the least deprived decile. Significantly higher inequalities (most vs. least deprived decile) in Long COVID existed in healthcare and patient-facing roles (aOR: 1.76; 95% CI: 1.27, 2.44), in the education sector (aOR: 1.68; 95% CI: 1.31, 2.16) and in women (aOR: 1.56; 95% CI: 1.40, 1.73) than men (aOR: 1.32; 95% CI: 1.15, 1.51). CONCLUSIONS: This study provides insights into the heterogeneous degree of inequality in Long COVID by deprivation, sex and occupation. These findings will help inform public health policies and interventions in incorporating a social justice and health inequality lens.

Reactions of industry and associated organisations to the announcement of the UK Soft Drinks Industry Levy: longitudinal thematic analysis of UK media articles, 2016-18.

BACKGROUND: The UK Soft Drinks Industry Levy (SDIL) was announced in March 2016, became law in April 2017, and was implemented in April 2018. Empirical analyses of commercial responses have not been undertaken to establish the scale, direction or nuance of industry media messaging around fiscal policies. We aimed to develop a detailed understanding of industry reactions to the SDIL in publicly available media, including whether and how these changed from announcement to implementation. METHODS: We searched Factiva to identify articles related to sugar, soft-drinks, and the SDIL, between 16th March 2016-5th April 2018. Articles included were UK publications written in English and reporting a quotation from an industry actor in response to the SDIL. We used a longitudinal thematic analysis of public statements by the soft-drinks industry that covered their reactions in relation to key policy milestones. RESULTS: Two hundred and ninety-eight articles were included. After the announcement in March 2016, there was strong opposition to the SDIL. After the public consultation, evolving opposition narratives were seen. After the SDIL became law, reactions reflected a shift to adapting to the SDIL. Following the publication of the final regulations, statements sought to emphasise industry opportunities and ensure the perceived profitability of the soft drinks sector. The most significant change in message (from opposition to adapting to the SDIL) occurred when the SDIL was implemented (6th April 2018). CONCLUSION: Reactions to the SDIL changed over time. Industry modified its media responses from a position of strong opposition to one that appeared to focus on adaptation and maximising perceived profitability after the SDIL became law. This shift suggests that the forces that shape industry media responses to fiscal policies do not remain constant but evolve in response to policy characteristics and the stage of the policy process to maximise beneficial framing.

Tax awareness and perceived cost of sugar-sweetened beverages in four countries between 2017 and 2019: findings from the international food policy study.

BACKGROUND: The public health benefits of sugar-sweetened beverage (SSB) taxes often rely on, among other things, changes to consumer purchases. Thus, perceived cost of SSBs and signalling effects-via awareness of the tax-may impact the effectiveness of SSB taxes on consumer purchases. OBJECTIVE: The study sought to examine perceived cost of SSBs, tax awareness, and changes in beverage purchasing over time and across four countries with and without SSB taxes. METHODS: The study used data from the 2017, 2018 and 2019 waves of the International Food Policy Study. Annual cross-sectional online surveys were conducted in Australia, Mexico, UK and US, which captured perceived cost of SSBs relative to non-SSBs in all countries (with Australia as a no-tax comparator), and measures of tax awareness and participants' reported changes in beverage purchasing in response to SSB taxes in Mexico (tax implemented in 2014), UK (tax implemented in 2018) and US (subnational taxes since 2015). Logistic regression models evaluated the measures across years and socio-demographic groups. RESULTS: Perceived cost of SSBs relative to non-SSBs was higher in Mexico (all three years) and the UK (2018 and 2019 following tax implementation) than Australia and the US. Tax awareness was higher in UK than Mexico, and decreased over time among Mexican respondents. Patterns of reported beverage purchasing changes in response to the tax were similar across Mexico, UK and US, with the largest changes reported by Mexican respondents. Respondents with characteristics corresponding to lower socioeconomic status were less likely to be aware of an SSB tax, but more likely to perceive SSBs to cost more than non-SSBs and report changes in purchasing in response to the tax, where there was one. CONCLUSIONS: This study suggests that in countries where a national SSB tax was present (Mexico, UK), perceived cost of SSBs and tax awareness were higher compared to countries with no SSB tax (Australia) or subnational SSB taxes (US), respectively, and suggests that perceived cost and tax awareness represent distinct constructs. Improving the 'signalling effect' of existing SSB taxes may be warranted, particularly in tax settings where consumer behaviour change is a policy objective.

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.

BACKGROUND: Restricting the advertisement of products with high fat, salt, and sugar (HFSS) content has been recommended as a policy tool to improve diet and tackle obesity, but the impact on HFSS purchasing is unknown. This study aimed to evaluate the impact of HFSS advertising restrictions, implemented across the London (UK) transport network in February 2019, on HFSS purchases. METHODS AND FINDINGS: Over 5 million take-home food and drink purchases were recorded by 1,970 households (London [intervention], n = 977; North of England [control], n = 993) randomly selected from the Kantar Fast Moving Consumer Goods panel. The intervention and control samples were similar in household characteristics but had small differences in main food shopper sex, socioeconomic position, and body mass index. Using a controlled interrupted time series design, we estimated average weekly household purchases of energy and nutrients from HFSS products in the post-intervention period (44 weeks) compared to a counterfactual constructed from the control and pre-intervention (36 weeks) series. Energy purchased from HFSS products was 6.7% (1,001.0 kcal, 95% CI 456.0 to 1,546.0) lower among intervention households compared to the counterfactual. Relative reductions in purchases of fat (57.9 g, 95% CI 22.1 to 93.7), saturated fat (26.4 g, 95% CI 12.4 to 40.4), and sugar (80.7 g, 95% CI 41.4 to 120.1) from HFSS products were also observed. Energy from chocolate and confectionery purchases was 19.4% (317.9 kcal, 95% CI 200.0 to 435.8) lower among intervention households than for the counterfactual, with corresponding relative reductions in fat (13.1 g, 95% CI 7.5 to 18.8), saturated fat (8.7 g, 95% CI 5.7 to 11.7), sugar (41.4 g, 95% CI 27.4 to 55.4), and salt (0.2 g, 95% CI 0.1 to 0.2) purchased from chocolate and confectionery. Relative reductions are in the context of secular increases in HFSS purchases in both the intervention and control areas, so the policy was associated with attenuated growth of HFSS purchases rather than absolute reduction in HFSS purchases. Study limitations include the lack of out-of-home purchases in our analyses and not being able to assess the sustainability of observed changes beyond 44 weeks. CONCLUSIONS: This study finds an association between the implementation of restrictions on outdoor HFSS advertising and relative reductions in energy, sugar, and fat purchased from HFSS products. These findings provide support for policies that restrict HFSS advertising as a tool to reduce purchases of HFSS products.

Understanding Marketing Responses to a Tax on Sugary Drinks: A Qualitative Interview Study in the United Kingdom, 2019.

BACKGROUND: The World Health Organization (WHO) recommends that countries implement fiscal policies to reduce the health impacts of sugary drinks. Few studies have fully examined the responses of industry to these policies, and whether they support or undermine health benefits of sugary drinks taxes. We aimed to explore the changes that sugary drinks companies may make to their marketing, and underlying decision-making processes, in response to such a tax. METHODS: Following introduction of the UK Soft Drinks Industry Levy (SDIL) in 2018, we undertook one-to-one semi-structured interviews with UK stakeholders with experience of the strategic decision-making or marketing of soft drinks companies. We purposively recruited interviewees using seed and snowball sampling. We conducted telephone interviews with 6 representatives from each of industry, academia and civil society (total n=18), which were transcribed verbatim and thematically analysed. Four transcripts were double-coded, three were excluded from initial coding to allow comparison; and findings were checked by interviewees. RESULTS: Themes were organised into a theoretical framework that reveals a cyclical, iterative and ongoing process of soft drinks company marketing decision-making, which was accelerated by the SDIL. Decisions about marketing affect a product's position, or niche, in the market and were primarily intended to maintain profits. A product's position is enacted through various marketing activities including reformulation and price variation, and non-marketing activities like lobbying. A soft drinks company's selection of marketing activities appeared to be influenced by their internal context, such as brand strength, and external context, such as consumer trends and policy. For example, a company with low brand strength and an awareness of trends for reducing sugar consumption may be more likely to reformulate to lower-sugar alternatives. CONCLUSION: The theoretical framework suggests that marketing responses following the SDIL were coordinated and context-dependent, potentially explaining observed heterogeneity in responses across the industry.

How should we evaluate sweetened beverage tax policies? A review of worldwide experience.

Over 45 jurisdictions globally have implemented sweetened beverage taxes. Researchers and policymakers need to assess whether and how these taxes change beverage demand and supply, their intended and unanticipated health, economic and equity impacts. Lessons from such evaluations can maximise the policies' success and impact on non-communicable disease prevention globally. We discuss key theoretical, design and methodological considerations to help policymakers, funders and researchers commission and conduct rigorous evaluations of these policies and related disease prevention efforts. We encourage involving the perspectives of various stakeholders on what evaluations are needed given the specific context, what data and methods are appropriate, readily available or can be collected within time and budget constraints. A logic model /conceptual system map of anticipated implications across sectors and scales should help identify optimal study design, analytical techniques and measures. These models should be updated when synthesising findings across diverse methods and integrating findings across subpopulations using similar methods.

Public acceptability of the UK Soft Drinks Industry Levy: repeat cross-sectional analysis of the International Food Policy Study (2017-2019).

OBJECTIVES: To determine whether public acceptability, in terms of both support for and perceived effectiveness of, the UK Soft Drinks Industry Levy (SDIL) changed between 4 months prior to, and 8 and 20 months after, implementation. DESIGN: Repeat cross-sectional online survey. SETTING: The UK. PARTICIPANTS: UK respondents to the International Food Policy Study aged 18-64 years who provided information on all variables of interest in November-December 2017 (4 months prior to SDIL implementation), 2018 (8 months after) or 2019 (20 months after; n=10 284). OUTCOME MEASURES: Self-reported support for, and perceived effectiveness of, the SDIL. RESULTS: The adjusted logistic regression model predicted that 70% (95% CI: 68% to 72%) of participants supported the SDIL in 2017, 68% (95% CI: 67% to 70%) in 2018 and 68% (95% CI: 66% to 70%) in 2019. There was no evidence of a difference in support in 2018 vs 2017 (OR: 0.93; 95% CI: 0.81 to 1.05); or in 2019 vs 2017 (OR: 0.90; 95% CI: 0.78 to 1.03). The adjusted logistic regression model predicted that 72% (95% CI: 70% to 74%) of participants perceived the SDIL to be effective in 2017, 67% (95% CI: 65% to 69%) in 2018 and 67% (95% CI: 64% to 69%) in 2019. There was evidence that perceived effectiveness decreased a small amount in 2018 vs 2017 (OR: 0.78; 95% CI: 0.69 to 0.88). The difference in 2019 vs 2017 was similar. CONCLUSIONS: We found high support for the SDIL among UK adults and this did not change between 4 months before implementation and 8 or 20 months after. While perceived effectiveness remained high, there was evidence that this decreased slightly after implementation in 2018, but no further in 2019. Greater understanding of influences on public acceptability of effective structural public health interventions is required.

Changes in soft drinks purchased by British households associated with the UK soft drinks industry levy: controlled interrupted time series analysis.

OBJECTIVE: To determine changes in household purchases of drinks and confectionery one year after implementation of the UK soft drinks industry levy (SDIL). DESIGN: Controlled interrupted time series analysis. PARTICIPANTS: Members of a panel of households reporting their purchasing on a weekly basis to a market research company (average weekly number of participants n=22 183), March 2014 to March 2019. INTERVENTION: A two tiered tax levied on manufacturers of soft drinks, announced in March 2016 and implemented in April 2018. Drinks with ≥8 g sugar/100 mL (high tier) are taxed at £0.24/L and drinks with ≥5 to <8 g sugar/100 mL (low tier) are taxed at £0.18/L. Drinks with <5 g sugar/100 mL (no levy) are not taxed. MAIN OUTCOME MEASURES: Absolute and relative differences in the volume of, and amount of sugar in, soft drinks categories, all soft drinks combined, alcohol, and confectionery purchased per household per week one year after implementation of the SDIL compared with trends before the announcement of the SDIL. RESULTS: In March 2019, compared with the counterfactual estimated from pre-announcement trends, purchased volume of drinks in the high levy tier decreased by 155 mL (95% confidence interval 240.5 to 69.5 mL) per household per week, equivalent to 44.3% (95% confidence interval 59.9% to 28.7%), and sugar purchased in these drinks decreased by 18.0 g (95% confidence interval 32.3 to 3.6 g), or 45.9% (68.8% to 22.9%). Purchases of low tier drinks decreased by 177.3 mL (225.3 to 129.3 mL) per household per week, or 85.9% (95.1% to 76.7%), with a 12.5 g (15.4 to 9.5 g) reduction in sugar in these drinks, equivalent to 86.2% (94.2% to 78.1%). Despite no overall change in volume of no levy drinks purchased, there was an increase in sugar purchased of 15.3 g (12.6 to 17.9 g) per household per week, equivalent to 166.4% (94.2% to 238.5%). When all soft drinks were combined, the volume of drinks purchased did not change, but sugar decreased by 29.5 g (55.8 to 3.1 g), or 9.8% (17.9% to 1.8%). Purchases of confectionery and alcoholic drinks did not change. CONCLUSIONS: Compared with trends before the SDIL was announced, one year after implementation, the volume of soft drinks purchased did not change. The amount of sugar in those drinks was 30 g, or 10%, lower per household per week-equivalent to one 250 mL serving of a low tier drink per person per week. The SDIL might benefit public health without harming industry. TRIAL REGISTRATION: ISRCTN18042742.

Evaluation of public health interventions from a complex systems perspective: A research methods review.

INTRODUCTION: Applying a complex systems perspective to public health evaluation may increase the relevance and strength of evidence to improve health and reduce health inequalities. In this review of methods, we aimed to: (i) classify and describe different complex systems methods in evaluation applied to public health; and (ii) examine the kinds of evaluative evidence generated by these different methods. METHODS: We adapted critical review methods to identify evaluations of public health interventions that used systems methods. We conducted expert consultation, searched electronic databases (Scopus, MEDLINE, Web of Science), and followed citations of relevant systematic reviews. Evaluations were included if they self-identified as using systems- or complexity-informed methods and if they evaluated existing or hypothetical public health interventions. Case studies were selected to illustrate different types of complex systems evaluation. FINDINGS: Seventy-four unique studies met our inclusion criteria. A framework was developed to map the included studies onto different stages of the evaluation process, which parallels the planning, delivery, assessment, and further delivery phases of the interventions they seek to inform; these stages include: 1) theorising; 2) prediction (simulation); 3) process evaluation; 4) impact evaluation; and 5) further prediction (simulation). Within this framework, we broadly categorised methodological approaches as mapping, modelling, network analysis and 'system framing' (the application of a complex systems perspective to a range of study designs). Studies frequently applied more than one type of systems method. CONCLUSIONS: A range of complex systems methods can be utilised, adapted, or combined to produce different types of evaluative evidence. Further methodological innovation in systems evaluation may generate stronger evidence to improve health and reduce health inequalities in our complex world.

Is Obesity Policy in England Fit for Purpose? Analysis of Government Strategies and Policies, 1992-2020.

Policy Points This analysis finds that government obesity policies in England have largely been proposed in a way that does not readily lead to implementation; that governments rarely commission evaluations of previous government strategies or learn from policy failures; that governments have tended to adopt less interventionist policy approaches; and that policies largely make high demands on individual agency, meaning they rely on individuals to make behavior changes rather than shaping external influences and are thus less likely to be effective or equitable. These findings may help explain why after 30 years of proposed government obesity policies, obesity prevalence and health inequities still have not been successfully reduced. If policymakers address the issues identified in this analysis, population obesity could be tackled more successfully, which has added urgency given the COVID-19 pandemic. CONTEXT: In England, the majority of adults, and more than a quarter of children aged 2 to 15 years live with obesity or excess weight. From 1992 to 2020, even though the government published 14 obesity strategies in England, the prevalence of obesity has not been reduced. We aimed to determine whether such government strategies and policies have been fit for purpose regarding their strategic focus, nature, basis in theory and evidence, and implementation viability. METHOD: We undertook a mixed-methods study, involving a document review and analysis of government strategies either wholly or partially dedicated to tackling obesity in England. We developed a theory-based analytical framework, using content analysis and applied thematic analysis (ATA) to code all policies. Our interpretation drew on quantitative findings and thematic analysis. FINDINGS: We identified and analyzed 14 government strategies published from 1992 to 2020 containing 689 wide-ranging policies. Policies were largely proposed in a way that would be unlikely to lead to implementation; the majority were not interventionist and made high demands on individual agency, meaning that they relied on individuals to make behavior changes rather than shaping external influences, and are thus less likely to be effective or to reduce health inequalities. CONCLUSIONS: The government obesity strategies' failure to reduce the prevalence of obesity in England for almost 30 years may be due to weaknesses in the policies' design, leading to a lack of effectiveness, but they may also be due to failures of implementation and evaluation. These failures appear to have led to insufficient or no policy learning and governments proposing similar or identical policies repeatedly over many years. Governments should learn from their earlier policy failures. They should prioritize policies that make minimal demands on individuals and have the potential for population-wide reach so as to maximize their potential for equitable impacts. Policies should be proposed in ways that readily lead to implementation and evaluation.