Award Title: Evaluation of the health impacts of the UK Treasury Soft Drinks Industry Levy (SDIL)
Funder: Department of Health and Social Care

Abstract: People who drink a lot of sugary drinks are more likely to develop tooth decay, obesity, diabetes and heart disease. Sugary drinks often contain lots of calories, and people can easily consume many calories from sugary drinks without feeling full. New UK guidance recommends that we consume less sugar than used to be the case._x000D_
In 2015, Public Health England said a tax on sugary drinks would be a way to help us all consume less sugar. In March 2016, the UK Government announced a tax on sugary drinks would start in April 2018. Details of the tax aren’t clear yet, but the tax will be higher for drinks with more sugar and will probably not apply to pure fruit juices. The two year delay is so that companies can reduce the amount of sugar in their drinks and avoid the tax. As no other country has tried this sort of tax, we don’t know what the effects will be._x000D_
We have talked to people working in government, public health, drinks companies and health advocacy groups. They think the tax will have all sorts of effects, and not just on health. Our study will look at the most important of these, tracking how things change over time. Studying a wide range of effects of the tax will help us be more certain that the results we see are true. For example, if purchases of sugary drinks, tooth decay and childhood obesity all go down, and purchases of other drinks go up, this will increase our confidence that the tax has had a positive impact on health._x000D_
Because we want to study how things have been changing since before the tax was announced to after it is implemented, we will mostly rely on information that is regularly collected by other organisations. This means we will be limited in what we can study. We will use data from supermarkets to explore the effects of the tax on the price, sugar content, and range of drinks available. We will use market research data to track changes in purchases of drinks. We will also study purchases of confectionary to see if people switch from sugary drinks to sugary foods. We will use government data to study effects of the tax on: diet, childhood obesity, and hospital admissions for tooth decay._x000D_
Any effects of the tax on what people eat and drink will take time to change their health. We will use advanced statistics (or ‘modelling’) to predict the effect of any changes in sugary drinks and diet on diseases and deaths 5-15 years later. From this, we will be able to predict financial savings for the NHS._x000D_
The tax’s effects might go beyond health. For instance, a healthier population should be more economically productive. Or people drinking less sugary drinks might mean fewer jobs in the food industry. We will use economics to predict the impacts of the tax on the whole UK economy._x000D_
We will also explore how different groups respond to the tax. We will conduct interviews and focus groups, and analyse newspapers and social media to explore how the public, politicians, public health professionals, and the sugary drinks industry feel about the tax. By studying these things over time we will be able to see, for example, whether any early opposition mellows over time._x000D_
In the UK, children drink more sugary drinks than adults. Obesity, heart disease, diabetes and tooth decay are more common in poorer people. Across all our work, we will look for any variations in effects between age groups, men and women, and levels of income._x000D_
Finally, we will engage the public and stakeholders in interpreting and sharing our findings.

Lay Abstract: We will conduct a natural experimental evaluation of proximal, intermediate & distal outcomes (work package (WP) 1), micro & macro-economic evaluation (WP3), & qualitative process evaluation (WP4) over 3 2-year time periods (2014-20). Simulation modelling of health & economic outcomes will focus on longer time horizons (WP2). In WP5, findings from WP1-4 will be synthesised and interpreted to refine intervention theory, and stakeholders engaged in dissemination._x000D_
WP1 – will use interrupted time series & regression analyses to evaluate impacts of the SDIL on:_x000D_
1.	Soft drink product diversification, formulation & price by brand, category & product size (volume) using data from 6 leading supermarket chains_x000D_
2.	Purchases of SSBs, all other drinks, confectionary & toiletries overall & by age, sex & socio-economic position (SEP), using household purchasing data from Kantar World Panel_x000D_
3.	Consumption of SSBs & confectionary overall & by age, sex & SEP using data from the National Diet & Nutrition Survey_x000D_
4.	Prevalence of childhood obesity using data from the National Child Measurement Programme & hospital admissions for severe dental caries using data from Hospital Episode Statistics (HES) overall & by age, sex & SEP._x000D_
WP2 – will adapt an existing life table model (PRIMEtime) for proportional multistate life table analyses. Data from WP1 will be used to estimate the effect sizes for SSB consumption & free sugars from drinks. We will estimate the impact of these changes on health outcomes over the short (5 years), medium (5-10 years) & long term (>10 years). Disease outcomes of interest will include dental caries, T2DM, cardiovascular & kidney disease, & obesity-related cancers (e.g. colon, kidney, liver, breast & pancreas)._x000D_
WP3 – will involve: (i) a micro-economic evaluation, modelling (using PRIMEtime) the health & social care cost impacts & health outcomes (QALYs gained); & (ii) a macro-economic evaluation, to assess the wider impacts of SDIL on industry, households, Treasury and UK economy._x000D_
In (i) NHS costs will be estimated using programme-budgeting & HES data. Social care & wider societal costs will be assessed overall & by age, sex, utility score & ICD10 codes. Data on dental caries & associated health care costs will be incorporated & we will extend the cost estimates to cover children & adolescents._x000D_
In (ii) we will use a Computable General Equilibrium (CGE) model of the whole economy that includes the cost minimising & profit maximising behaviour of producers, consumption & saving behaviour of households & government, taxation mechanisms & the use of labour, capital & other factors in order to produce goods & services for investment or consumption, & includes trade across international borders._x000D_
WP4 – will use qualitative methods to determine the perceived acceptability & impacts of the SDIL. We will conduct thematic Framework analysis of interviews with professionals & focus groups with the public, thematic content analysis of newspapers articles & social media (twitter) output & analysis of survey questions on consumer attitudes to SSBs collected by Kantar in their household purchasing panel._x000D_
WP5 – will involve synthesis of the findings from WPs1-4 using our systems map & refinement of intervention theory. Triangulation of evidence generated using different methods from WPs1-4 will facilitate corroboration of findings, supported by techniques such as pattern matching. We will engage stakeholders in dissemination.

Research Activity Codes: 3.1 PRIMARY PREVENTION INTERVENTIONS TO MODIFY BEHAVIOURS OR PROMOTE WELL-BEING
Health Categories: CANCER AND NEOPLASMS;CARDIOVASCULAR;METABOLIC AND ENDOCRINE;ORAL AND GASTROINTESTINAL;STROKE