The CHEPI seminar series showcases the research of leading academics from across the Centre, Imperial College, and our colleagues in other universities. Seminars feature both finished papers as well as work in progress and are a place to learn about novel methodologies, share insights and support ongoing research across the field of health research and policy. All research staff, Faculty and PhD students are welcome to attend.
For further information, including to be added to our mailing list and to suggest a speaker, please contact Mario Martinez-Jimenez (email@example.com).
Gabriella Conti, Professor of Economics, University College London
Bernardo Andretti, Research Fellow at University College London
Title: Demand-Side Nutritional Inequality? How Poverty and Wealth Shape Healthy Eating
Abstract: Poor consumers around the world display unhealthier diets than the wealthy. This nutritional inequality is often attributed to supply-side factors such as the higher prices and the lower availability of healthy foods in deprived neighborhoods. The current research assesses whether this global phenomenon can also be explained by differences in food preferences across the socioeconomic spectrum—a demand-side account. In a series of five pre-registered studies in a highly unequal environment (Rio de Janeiro, Brazil), it investigates whether low- (vs. high-) SES consumers (a) vary in food preferences over and above supply-side considerations, (b) give different weights to critical food attributes (fillingness, healthiness and taste) and (c) perceive the association among these attributes differently. Results show that compared to the wealthy, low-SES consumers are more likely to choose unhealthy items even when supply-side factors are controlled by design, are much more likely to prioritize fillingness at the expense of healthiness, and tend to see healthy items as less filling and tasty. Based on these findings, the final policy-related study shows that it is possible to increase healthy food choices among the poor by increasing the perception of fillingness of the healthy options available.
Charitini Stavropoulou, Reader in Health Services Research, City, University of London
Title: Funding of Early Career Researchers: Evidence from the UK’s Medical Research Council
Authors: Dr Charitini Stavropoulou (City, University of London) and Dr Ian Viney (Medical Research Council)
Abstract: We investigate the effect of public funding on early career researchers, defined as those applying to secure their first grant as Principal Investigators. Using data from both successful and unsuccessful candidates, who applied to the UK’s Medical Research Council between 2006 and 2016, we explore the impact of funding on research grants and publication outcomes in the years that follow their submission. Applying propensity score weighting, our results provide evidence that successful candidates accumulate more external funding post submission than those who were not successful. In terms of publications, receiving an award does not increase the volume of publications and citations. Yet, when the analysis is done by gender, we find that successful female applicants are better cited in their field and produce more senior author publications. When looking into ethnicity, successful applicants from Black, Asian and Ethnic Minority background produce publications with higher outreach than white researchers. This is the first counterfactual study on this topic that goes beyond scientific productivity and provides evidence of a gender and ethnicity effect of funding in scientific influence of young researchers.
Maxime Roche, PhD student, Imperial College Business School
Title: Can value-added taxes promote healthier diets? An ex-ante evaluation in Costa Rica
Abstract: In February 2023, Costa Rica implemented a new basic tax basket of foods (CBT in Spanish) on which a reduced value-added tax (VAT) rate applies to promote a more balanced diet. This paper aims to estimate how prices impact food demand and assess ex-ante the impact of the new CBT on household spending and nutrient availability across income groups and food processing levels. Other scenarios are compared including a CBT based on nutrient profile modelling. Own- and cross-price elasticities are estimated using the National Household Income and Expenditure Survey and a two-step censored quadratic almost ideal demand system model accounting for price and total expenditure endogeneity. Food groups account for food processing levels using the NOVA classification. Nutritional information is derived from a Food Composition Table. Within food groups, processed and ultra-processed foods are the most price-elastic. The new CBT is associated with no significant improvements in nutrient availability. Conversely, the VAT scenario based on nutrient profile modelling is associated with reductions in critical nutrients, with lower-income households benefiting from relatively higher reductions. The impact on total household spending is limited. Differentiated VAT rates based on nutrient profile modelling could discourage the purchase of ultra-processed foods and have significant nutritional benefits. Further research should assess the tax revenue impact of the proposed fiscal policies.
Matteo M Galizzi, Associate Professor of Behavioural Science, London School of Economics
Title: What have we learned from behavioural economics for the COVID-19 responses?
Abstract: The COVID-19 pandemic has provided an unprecedented opportunity for behavioural economics (that is, the interdisciplinary field that combines and cross-fertilises insights from economics and psychology) to make a difference for future pandemic responses. We try to systematically distil the key lessons we have learnt from behavioural economics during the COVID-19 pandemic and the subsequent policy responses. There are three main take-home lessons that could help advance our understanding of human behaviour in a time of a pandemic and enhance the preparedness of international institutions and governments for future pandemics: i) we should fully account for the heterogeneity in preferences and attitudes, beliefs and perceptions, decisions and biases; ii) we should acknowledge that, besides citizens and patients, policy-makers and ‘experts’ can make biased decisions too: we should therefore employ a full and diverse spectrum of behavioural interventions - going beyond ‘nudges’ when needed - and we should acknowledge that individual responses to such interventions are inherently heterogeneous as well; and iii) as it is not clear upfront what will work for whom, for future pandemic responses we should engage more systematically with randomised controlled experiments and with collaborative, transparent evaluations of reproducible scientific evidence.
Elisa Pineda, Research Fellow, Imperial College London
Title: Healthy and environmentally sustainable food environments: A multiphase optimization strategy and randomised controlled trial intervention in Mexico
Abstract: Mexico has one of the highest rates of obesity worldwide—75% of the population presents obesity or overweight. Diet-related non-communicable diseases (NCDs) are particularly high in the north of the country where the Sonoran Desert is located. The Sonoran Desert borders the US and is therefore greatly influenced by the US diet. Dietary fat consumption in the region is 200% above the dietary guidelines. In addition, high temperatures and water scarcity facilitate a high sugar-sweetened beverage consumption. In 2012, the average population in Mexico drank 163L of sugar-sweetened beverages a year.
The in-store food environment, which refers to the availability, price, promotion, and nutritional quality of food products available within stores, can influence consumers’ food choices through the visibility, cost, and marketing of food. Consumer food choices also have an impact on the environment. One-third of global green gas emissions come from the food system. The processing of food, its transport, packaging, storage, and distribution contribute to the environmental impact of food. Although some nutritional quality of food products is known to consumers through nutritional labelling, information about the healthiness and environmental impact of the in-store food environment and available products is unknown in Mexico. This study aims to evaluate the healthiness and environmental impact of food choices within the in-store food environment of supermarkets in the Sonoran Desert in Mexico. The local social, political, economic, and cultural context will be considered to adapt existing evidence-based food choice architecture strategies to enable healthy and low carbon-footprint food choices within local supermarkets for the prevention of diet related NCDs and of global warming mitigation. The research project is subdivided into four main phases: Phase 1) an initial food environment evaluation, Phase 2) a stakeholder workshop, Phase 3) an optimization phase and Phase 4) a randomised controlled trial (RCT). The initial food environment evaluation will consist of secondary data collection to assess the status quo of the retail food environment in the Sonoran Desert. This will be undertaken by collecting data on product type, nutritional quality, environmental impact, price, promotion, placement and sales of food and beverage products available in local food stores in the city of Hermosillo in the Sonoran Desert Region of Mexico. The stakeholder workshop will target the identification of perspectives, barriers, and opportunities in relation to the food environment in the Sonoran Desert Region of Mexico for the prevention of obesity and mitigation of global warming. During the optimisation phase, a pilot will be undertaken in local supermarkets to enhance the saliency of targeted healthy and low carbon footprint food items. Purchase of targeted food items before, during and after pilot will be assessed. The results of the pilot will serve to adapt a RCT. This project will provide evidence to help guide food environment policies and programmes in Mexico leading to the advancement of Mexico’s obesity and global warming mitigation strategies.
Matthias Hofer, Research Associate, Imperial College Business School
Title: Developing evidence-based policy recommendations to improve the competitiveness of the UK pharma/biopharma sector
Abstract: We report on initial findings from research funded by the Gatsby Foundation to find ways of improving the competitiveness of the UK biopharma/pharma sector. There is strong international competition over R&D investment and the location of drug manufacturing. In the United Kingdom (UK), the pharmaceutical industry employed 66,000 people, invested approximately £ 5 billion in R&D in 2020, and is responsible for approximately 18% of total UK industrial R&D spending. In the first phase of the study, data was collected on the structure of the sector and its performance to identify strengths, weaknesses, threats and opportunities. The UK has an internationally strong R&D environment with public and private finance mechanisms. Two global companies, AstraZeneca and GSK, are headquartered in the UK. While these dominate the economic and R&D performance of the sector, there is a large number of small and young companies with high R&D activity, with the potential for future economic impact. These are clustered around scientific hubs to share and develop technologies. However, the sector also faces risks from the decline in access to talent, R&D infrastructure, trade, and manufacturing capabilities. Brexit also led to uncertainties, including regulatory divergence and additional regulatory burden, which could have an impact on R&D activity as well as access to medicines. This presentation will provide an overview of the study and its progress in developing policy recommendations for industry and government.
Ellen Green, Associate Professor, College of Health Solutions, Arizona State University
Title: Subjective expectations and uncertainty: A study of the deceased-donor transplantation process
Abstract: Identifying allocation mechanisms to reduce the discard rate of deceased-donor kidneys is a focus of policy makers; however, many of the leading solutions assume strategic behavior with full information. We constructed a novel data set to investigate the accuracy of surgeon beliefs. We then study the extent that inaccurate beliefs factored into doctors' decision to accept a deceased-donor kidney between January 1, 2016 and December 31, 2020. Overall, we found that doctors' beliefs about patient outcomes based on deceased-donor kidney quality was heterogeneous across doctors, while patient outcomes did not differ. We then showed that doctors' beliefs predicted acceptance rates. Those whose predictions about outcomes deviated from the objective data more were less likely to accept a deceased-donor kidney. Our results suggest that doctors lack some of the appropriate information to behave strategically and caution the implementation of proposed mechanisms because the underlying assumptions used in their analysis may not hold.
Xinrong Zhu, Assistant Professor in Marketing, Imperial College London
Title: Inference and Impact of Category Captaincy
Abstract: This paper studies category captaincy, a vertical relationship whereby retailers delegate pricing and assortment decisions of an entire product category to one of the leading manufacturers within the category. These confidential contracts have raised anti-trust concerns, however, empirical analysis has been limited. I develop strategies to infer the prevalence of such contracts and to quantify their impact on prices, market shares, and profits of manufacturers and retailers. I apply my strategies to the yogurt category, where the captain is either Dannon or Yoplait---the top two national brands. My approach is to first estimate a random-coefficient demand model using Nielsen scanner data. I use estimates of the brand-retailer specific shocks to classify retailers into one of three categories: Dannon-captained retailers, Yoplait-captained retailers, or non-captained retailers. I then apply conduct tests to infer that captains eliminate double markups from their own products, while the non-captain products still have double markups. My results suggest that about 70% of retailers engage in captaincy arrangements. Finally, counterfactual experiments show that category captaincy relationships increase the market share of the captain by about 50%, but they can also increase retailer profits and consumer welfare by eliminating double markups on the captain’s products.
Sarah Mounsey, Post-doctoral Research Associate in Economics, Imperial College London
Title: Fiji’s SSB tax: a mixed method analysis
Abstract: Globally, health taxes have proved a popular and effective intervention for reducing non-communicable disease (NCDs). Specifically, implementation of taxes on SSBs/energy-dense food has significantly increased in the last two decades in countries around the world. With their implementation, several parallels to tobacco and alcohol taxes can be seen. First, these taxes are recommended as part of a comprehensive package of policy tools targeting reduced consumption. Second, they have been largely successful in reducing demand and hence diet-related NCD risk factors and third, they are effective at generating significant revenue. Despite the growing number of governments adopting this administratively feasible policy tool there are still policy makers who hesitate, primarily due to uncertainty around industry claims of job loss and economic downturn. Furthermore, industries involved in the manufacture and supply of these products fiercely oppose taxes based on the broad argument of decreased sales and thus, reduced profits. Evidently, this creates a tension between health and economics goals. Thus, effective and sustainable design and implementation of health taxes must be underpinned by a more nuanced understanding of the political and economic drivers influencing the policy process and the key actors involved as well as evidence of potential change associated with the policy. This presentation highlights how industry, with a narrow goal of financial profit, creates and influences significant and wide-ranging opposition for the effective implementation of health and fiscal policy. Then, for a case study country (Fiji), the presentation explores findings from analyses of policy, political economy analysis. corporate political activity and modelling, opportunities for policy makers to strengthen and/or scale up fiscal policy interventions despite the negative industry influence. The presentations illustrate important lessons for similar settings seeking to strengthen or scale-up the impact of diet-related fiscal policy.
Stephen Jan, Professor of Health Economics, George Institute
Time: 13:30 – 14:30
Title: Promoting the agenda for universal health coverage: What evidence do we need?
Abstract: Universal health coverage – the ideal that citizens have access to health services of reasonable quality – is a common goal across health systems around the world. It is embedded in the UN 2030 Sustainable Development goals and in 2023 the UN General Assembly will host its Second High Level Meeting on Universal Health Coverage. The presentation will provide an overview of a long-term research program aimed at informing policies and programs to work to toward this goal. An outline of a series of studies conducted across different disease areas and across different settings will be presented. The focus of this work has been to assess the financial burden of chronic diseases and related questions about the impact of such costs on outcomes such impoverishment, treatment abandonment, their differential impact across population groups, the potential for health insurance coverage to protect against such impacts and the effect of specific program and policies on some of these outcomes. The presentation will present an agenda for research spanning observational studies, evidence reviews and impact evaluations to identify measures needed to expand access to care and achieve the policy goal of universal health coverage.
Mujaheed Shaikh, Professor of Health Governance, Hertie School
Title: Vaccination mandates: A double-edged sword
Abstract: While countries directed unprecedented efforts towards the development and rapid administration of vaccines against COVID-19, population coverage rates remain suboptimal. In the United States, despite early access, sufficient supply and a swift initial roll-out of vaccines, large disparities between counties were quickly visible. Where recommendation policies have not been successful in incentivizing vaccination behaviours, health systems have enacted a range of instruments ranging from vaccine passports for international travel and access to public spaces, to employer vaccine mandates. Despite public opposition, several countries have introduced vaccine mandates differing in their scope as well as strictness. In this study, we assess the effect of vaccination mandates on vaccination uptake taking advantage of the staggered roll-out of vaccine mandates for state employees across states in the US. The variation in the timing of implementation of the mandates enables us to estimate the causal impact of vaccination mandates on vaccination uptake using a difference-in-differences approach. We also examine heterogeneity in the effect of vaccine mandates by race, income, education and household difficulty in meeting expenses. Finally, we investigate potential mechanisms and present evidence of the role of trust and the specific design of the vaccine mandate policy in the US that can explain our findings.
Katharina Blankart, Assistant Professor at the Faculty of Business Administration and Economics, University of Duisburg-Essen
Title: The effects of off-label drug use on disability and health care use
Abstract: In 2015, 44% of prescriptions consumed by non-institutionalized Americans were used for off-label indications. We exploit a novel publicly available data source that links health conditions to indicated medical treatments by active pharmaceutical ingredient to data that captures health care use and disability according to the Medical Expenditure Panel Survey. Using drugs on-label compared to off-label use substantially reduces health care use and disability. Off-label use is substantially higher in smaller markets by number of individuals and use in children or adolescents compared to adults, confirming previous findings that incentives to innovate are stronger in larger markets. Full link could be found here: https://uni-duisburg-essen.sciebo.de/s/BodKwWQ5Q5LiFZU
Jackie Bertoldo, Associate Director of Nutrition & Food Choice Architecture, Stanford University
Title: Transforming University Food Systems: Cultivating the Long-Term Well-Being of People and the Planet – One Student, One Meal at a Time
Abstract: The Menus of Change University Research Collaborative (MCURC), co-founded by Stanford University and the Culinary Institute of America, is a nationwide network of colleges and universities using campus dining halls as living laboratories for behavior change. These are dynamic learning environments where applied research is bridged with operational innovation to advance the Menus of Change Principles of Healthy, Sustainable Menus. Together we serve over 800,000 meals each day, representing 15 billion meals over the course of our students’ lifetimes. They will be tomorrow’s leaders, parents, consumers, and citizens. The impact we have on their eating habits will not only have a tremendous impact today, but can transform the food system for the future. Our groundbreaking research pipeline focuses on plant-forward diets, food waste reduction, and the drivers of consumer food choices. We also co-create educational resources related to accelerating the implementation of the Menus of Change Principles of Healthy, Sustainable Menus across the foodservice industry. The Collaborative is an extension of Menus of Change®: The Business of Healthy, Sustainable, Delicious Food Choices, a groundbreaking initiative from The Culinary Institute of America and Harvard T.H. Chan School of Public Health. Menus of Change works to realize a long-term, practical vision integrating optimal nutrition and public health, environmental stewardship and restoration, and social responsibility concerns within the foodservice industry and the culinary profession.
Mario Martinez-Jimenez, Visiting Researcher, Imperial College London
Title: The Long-term Effects of Parental Unemployment
Abstract: While the effects of unemployment on the health of the unemployed is well-documented, its long-term spillover effects on the health of their relatives, especially children, remain poorly understood. This research focuses on the effects of parental unemployment spells experienced during early, mid and late childhood on the long-term children’s mental and physical health. The analysis exploits data drawn from the British Household Panel Survey (BHPS) and the UK Household Longitudinal Study (UKHLS), linking detailed parental socioeconomic information with their children. This paper employs a Correlated Random Effects (CRE) probit model that allows accounting for unobserved heterogeneity as well as a non-linear Generalized Estimating Equations (GEE) random effects estimator accounting in addition for the dependency structure of the data. Results indicate that experiencing parental unemployment during early and late childhood has a negative effect on the children’s likelihood of suffering from long-standing illnesses later in life, while experiencing parental unemployment during middle childhood affects the young adult’s mental health negatively. Moreover, experiencing parental unemployment during late childhood increases the probability of both reporting poor or fair self-assessed health and the likelihood of consume prescribed medicines in early adulthood. However, there seems to be a considerable effect heterogeneity by family socioeconomic status and parent’s gender, whereas frequencies of parental unemployment spells appear to be a potential mechanism affecting overall results. These results may help policymakers shaping appropriate policy responses to mitigate the psychological and physical burden derived from parental unemployment, especially among already disadvantaged households.
Stijn Maesen, Assistant Professor of Marketing, Imperial College London
Title: How product characteristics influence the sales impact of front-of-pack health symbols
Abstract: Manufacturers increasingly adopt health symbols, which translate overall product healthiness into a single symbol, to communicate about the overall healthiness of their grocery products. This study examines how the performance implications of adding a front-of-pack health symbol to a product vary across products. We study the sales impact of a government-supported health symbol program in 29 packaged categories, using over four years of scanner data. The results indicate that health symbols are most impactful when they positively disconfirm pre-existing beliefs that a product is not among the healthiest products within the category. More specifically, we find that health symbols are more effective for (i) products with a front-of-pack taste claim, (ii) lower priced products, and (iii) private label products. Furthermore, these results are more pronounced in healthier categories than in unhealthier categories. Our findings imply that health symbols can help overcome lay beliefs among consumers regarding a product’s overall healthiness. As such, adding a health symbol provides easy-to-process information about product healthiness for the consumer and can increase product sales for the manufacturer.
Prof. James Barlow
Title: Is ‘repurposing’ old drugs a new innovation strategy for the pharmaceutical industry?
Alexa Segal and Dr Kelsey Case
Title: Did it work? An evaluation of the Bermuda Discretionary Foods Tax
Dr Cristina Taddei
Title: Worldwide trends in blood lipids from 1980 to 2018
Dr Luigi Siciliani (Journal of Health Economics)
Title: How to publish in health economics? An editor's perspective
Dr Stephan Seiler (Imperial College Business School)
Title: The Impact of Soda Taxes: Pass-through, Tax Avoidance, and Nutritional Effects
Dr Zoë Mullan (Lancet Global Health)
Title: Global health according to The Lancet Global Health
Dr Laure de Preux
Title: Mobility and socio-economic factors during the COVID-19 pandemic
Dr Carmen Huerta & Dr Verena Zuber
Title: Does poor physical health reduce social mobility? Evidence from longitudinal and Mendelian randomization analyses using data from two UK cohorts