How can tobacco policy models quality be assessed: a systematic review

 

Policy simulation models (PSMs) have been used extensively, both to shape health policies before real-world implementation and to evaluate post-implementation impact. However, an accepted quality assessment framework for simulation models is lacking. This systematic review aimed to develop a novel quality assessment framework for tobacco control PSMs. We searched five databases to identify peer-reviewed tobacco control PSMs that projected tobacco-use and tobacco-related outcomes from smoking policy scenarios. We extracted information on modelling inputs, structure and outputs. Using our proposed quality assessment framework, we scored models on nine dimensions: representativeness of population, policy effectiveness evidence, simulated smoking histories, simulated smoking-related diseases, exposure-outcome lag time, transparency, sensitivity analysis, validation and equity. We then compared the model score with the number of cited papers using each model. The results were narratively presented. After screening 5046 candidate papers; 145 papers were included and categorised into 25 PSMs. After scoring the models using our proposed framework, we observed that seven models were given seven and more points. The higher-scored models were generally those with a higher number of publications. While all included models had been subject to sensitivity analysis, other best practices were often lacking. Nine models did not explicitly consider smoking-related diseases. Smoking histories were commonly collapsed into crude smoking status categories rather than reflecting smoking intensity or quitting history. Furthermore, only four models estimated policy equity impact. Our systematic review revealed a variety of modelling techniques used in tobacco control. Our novel quality assessment framework offers a potential quality measure for tobacco control policy simulation models. It may guide health decision modellers and inform health policymaking.

Key messages

All nine framework dimensions were observed in two tobacco control PSM, suggesting the framework relevance and feasibility. However, few models achieved high scores in all dimensions. This novel quality assessment framework aims to support the development and sharing of good modelling practice and thus promote better health policy decision-making.

Impacts of post-Brexit agricultural policy on fruit and vegetable intake and cardiovascular disease

Background

The post-Brexit agricultural regime represents an opportunity to positively influence food systems and improve public health. Health-improving measures could include expanding the UK production of fruits and vegetables (F&V), thus increasing F&V availability. Currently, only 1.4% of total agricultural land in England is allocated to F&V. This study aims to estimate the potential impacts of allocating additional land to F&V production on cardiovascular disease (CVD) and inequalities in England between 2021 and 2030.

Methods

We used the previously validated IMPACT Food Policy model to translate changes in land allocated to F&V into changes in F&V intake and associated CVD mortality, expressed in number of deaths prevented or postponed (DPPs) by age, sex, and Index of Multiple Deprivation (IMD) quintile. We modelled two scenarios that assumed a linear increase in agricultural land allocated to F&V until it covers a) 10% and b) 20% of all land suitable for production of horticultural crops in England. We assumed that F&V prices would drop to a new equilibrium. We used Monte Carlo simulations to produce uncertainty intervals.

Results

Our model suggested that by 2030, F&V intake might increase by approximately 4% (95% Uncertainty Interval: 2%-7%) and 8% (4%-13%) respectively, under the first scenario. Under the second scenario, F&V intake could increase by approximately 17% (10%-29%) and 37% (26%-51%) respectively. These increases in F&V intake were associated with 3360 (1760-5920) CVD DPPs under the first scenario and 15700 (9000-24310) under the second scenario in 2021-2030. Our modelled scenarios could also reduce inequalities, with some 16% of DPPs occurring in the least deprived group compared with 22% in the most deprived.

Conclusions

Policymakers should consider the public health impacts of the post-Brexit agricultural regime in England. Increasing the land allocated to F&V production could substantially reduce the burden of CVD and associated inequalities.

Key messages

The post-Brexit agricultural policy can be an opportunity to improve diet and public health in the UK. Increasing the agricultural land allocated to fruit and vegetable production in England could reduce the burden of cardiovascular disease and associated inequalities.

Umbrella review of strategies to improve uptake of screening programmes

Introduction

High participation rates in screening programmes targeting non-communicable diseases are instrumental in achieving full screening benefits; however, screening programmes remain underused, especially among vulnerable populations. We conducted an umbrella review to assess the type of approaches screening programmes use to maximise uptake, the effectiveness of the approaches and the impact on equity.

Methods

Electronic databases were searched (1999-2019) for systematic reviews on approaches aimed at improving uptake of screening programmes for adults in middle- and high-income countries, with participation rate as the primary outcome. A narrative synthesis was undertaken to present the results by strategy, screening programme and strength of evidence. This study was registered in PROSPERO [CRD42019132087].

Results

In total, 3,059 records were identified, and 82 systematic reviews were included. Preliminary findings suggest contradictory evidence, and effectiveness appears to depend on the disease screened for and specific program implementation. Invitation methods including letters and direct reminders seem to work universally. However, combined approaches using access-enhancing, individual- and system-directed strategies seem to be more effective than single approaches such as invitation methods alone. Few studies evaluated the impact on equity.

Conclusions

Strategies to improve uptake of screening programmes have the potential to be effective. However, there are many components within the system, either at individual, health care professional or health care system level that can influence uptake of screening programmes. Within each screening programme, it is likely that a range of interventions is needed to improve the uptake as opposed to a single intervention.

Key messages

Improving uptake of screening programmes is a complex issue with many factors influencing the process. A range of interventions is favoured over single interventions.

IMPACT: A Generic Tool for Modelling and Simulating Public Health Policy

Background: Populations are under-served by local health policies and management of resources. This partly reflects a lack of realistically complex models to enable appraisal of a wide range of potential options. Rising computing power coupled with advances in machine learning and healthcare information now enables such models to be constructed and executed. However, such models are not generally accessible to public health practitioners who often lack the requisite technical knowledge or skills.

Objectives: To design and develop a system for creating, executing and analysing the results of simulated public health and health-care policy interventions, in ways that are accessible and usable by modellers and policy-makers.

Methods: The system requirements were captured and analysed in parallel with the statistical method development for the simulation engine. From the resulting software requirement specification the system architecture was designed, implemented and tested. A model for Coronary Heart Disease (CHD) was created and validated against empirical data.

Results: The system was successfully used to create and validate the CHD model. The initial validation results show concordance between the simulation results and the empirical data.

Conclusions: We have demonstrated the ability to connect health policy-modellers and policy-makers in a unified system, thereby making population health models easier to share, maintain, reuse and deploy.