Methodological development in whole-economy modelling: P. falciparum malaria control in Africa

Lead Research Organisation: London Sch of Hygiene and Trop Medicine
Department Name: Public Health and Policy

Abstract

The demand for economic evidence by policy makers is strong and increasing, used to indicate the relative burden of diseases, the distribution of that burden, and the desirability of specific interventions to affect disease. Such evidence is overwhelmingly generated by studies that measure affects upon individuals, households and the health sector and then scale these up to represent national impacts. However, such analysis is limited in exploring fully the economic impact of a disease with widespread effects, such as malaria, which impacts upon the economy from a number of angles, such as labour supply, tourism and foreign investment. Previous work has demonstrated the value of the Computable General Equilibrium (CGE) approach to modeling these wider effects, but highlighted the need for further development in its application to health issues; specifically, integration of the economic modeling with the epidemiology and demography of disease.

Malaria control in Africa provides the ideal case-study for this methodological developmental work, as it is one of the most common global infectious diseases. Africa especially is heavily affected, and economic analyses of malaria and malaria control policies have been demonstrated to have limitations. Indeed, it has been recently suggested that ?more robust analysis, taking into account factors such as effect on tourism and investment, should be a research priority? (Lancet, 2008; 371: 1634). The developmental work proposed here will take place in Ghana and Mozambique, which reflect the East-West regional differences in malaria epidemiology.

Overall, this project will produce a model of malaria (control) applicable across a range of African counties. Together with existing work, this project will further contribute to a modeling capability applicable across a wide range of infectious diseases, causative agents and developed and developing countries, facilitating the wider application of this form of modeling within health economics, and increasing its relevance to health policy.

Technical Summary

The demand for economic evidence by policy makers is strong and increasing, used to indicate the relative burden of diseases, the distribution of that burden, and the desirability of specific interventions to affect disease. Such evidence is overwhelmingly generated by partial-equilibrium studies, based on analyses of economic effects upon individuals, households and the health sector. Such analysis is limited in exploring fully the economic impact of a disease with system-wide effects, such as malaria. Alternative, whole-economy analyses (considering impacts on national economic indicators and across non-health related sectors) have tended to be undertaken by development economists, typically using a health proxy as an explanatory variable in economic growth models, limiting opportunities to fully analyze the complex relationship between health, other aspects of the economy and broader economic indicators. Previous work has demonstrated the value of the Computable General Equilibrium (CGE) approach to whole-economy modeling, but highlighted the need for further development in its application to health issues; specifically, endogenization of the epidemiology and demography of disease.

P. falciparum malaria control in Africa provides the ideal case-study for this methodological developmental work, as one of the most common global infectious diseases. Africa especially is heavily affected, and economic analyses of malaria and malaria control policies have demonstrated the limitations of both partial-equilibrium and cross-country econometric analyses. Indeed, Feachem and Sabot recently suggested that ?more robust analysis, taking into account factors such as effect on tourism and investment, should be a research priority? (Lancet, 2008; 371: 1634). The developmental work proposed here will take place in Ghana and Mozambique, as these reflect the East-West regional differences in malaria epidemiology.

Overall, this project will produce a dynamic CGE model of malaria (control) applicable across a range of African counties. Together with existing work, this project will further contribute to a modeling capability applicable across a wide range of infectious diseases, causative agents and developed and developing countries, facilitating the wider application of this form of modeling within health economics, and increasing its relevance to health policy.

Publications

10 25 50
 
Description Department of Health Policy Research Programme
Amount £89,973 (GBP)
Funding ID 080/0007 
Organisation Department of Health (DH) 
Sector Public
Country United Kingdom
Start 02/2011 
End 09/2011
 
Description Janssen R&D Project
Amount $162,632 (USD)
Organisation Janssen Research & Development 
Sector Private
Country Global
Start 11/2014 
End 05/2015
 
Description NIHR Public Health Research
Amount £149,895,615 (GBP)
Organisation National Institutes of Health (NIH) 
Sector Public
Country United States
Start 07/2017 
End 12/2021
 
Description Palm Oil: Sustainability, Health and Economics
Amount £200,000 (GBP)
Funding ID 103905/Z/14/Z 
Organisation Wellcome Trust 
Department Wellcome Trust Bloomsbury Centre
Sector Academic/University
Country United Kingdom
Start 09/2016 
End 12/2017
 
Description SUSTAINING HEALTH AWARD
Amount £263,491 (GBP)
Organisation Wellcome Trust 
Sector Charity/Non Profit
Country United Kingdom
Start 09/2014 
End 08/2016
 
Title CGE Model for Ghana 
Description An extension of the IFPRI Standard CGE model to incorporate a reversible catalytic model of malaria and to utilise the malaria focused Ghana SAM (also mentioned in this section). 
Type Of Material Computer model/algorithm 
Provided To Others? No  
Impact The development of this database attracted the attention of the Ghana Statistical Service and provoked their invitation to participate in their Africa Statistics Day celebrations as outlined in the earlier section of this submission. 
 
Title Ghana SAM 
Description A Ghana Social Accounting Matrix with households disaggregated by malaria prevalence and gender of head of household. 
Type Of Material Database/Collection of data 
Provided To Others? No  
Impact The development of this database attracted the attention of the Ghana Statistical Service and provoked their invitation to participate in their Africa Statistics Day celebrations as outlined in the earlier section of this submission. 
 
Title Integrated Ghana Model 
Description An extension of the CGE Model for Ghana (also listed in this section). The Integrated Ghana Model integrates the reversible catalytic model of malaria, demographic population model and macroeconomic CGE model in a single framework. This model was presented at the 2013 validation workshop in Ghana mentioned in the Engagement Activities section and has since been extended to incorporate additional feedback effects including private expenditure on healthcare interventions. 
Type Of Material Computer model/algorithm 
Provided To Others? No  
Impact Papers for the draft 2013 model have been presented at conferences including ASTMH, HESG and GTAP. Publications are in progress for the public dissemination of the final modelling methodology and applications. 
 
Title Integrated Tanzania Model 
Description This model is an adaptation of the Ghana integrated model to a second country- Tanzania. 
Type Of Material Computer model/algorithm 
Provided To Others? No  
Impact Publication of applications using the Ghana model are in progress to demonstrate the proof of concept. Additional applications using the Tanzania model will follow. 
 
Title Malaria Focused Ghana Sam 
Description This new Malaria-focussed 2004 Ghana SAM was constructed on the basis of the original 2004 Ghana SAM. The crucial difference is that the new Malaria-focussed SAM includes a new household breakdown with 19 household types which are categorised according to the 19 geographical areas from the Demographic model: one GAMA household + 18 household types categorised according to rural-urban location, three ecological zones (Coastal, Forest, Savannah), and three malaria transmission intensity levels (low, medium, high human prevalence - human prevalence is closely correlated with location-specific EIR values, and is therefore a good proxy for transmission intensity). The final 2004 Malaria-focussed SAM included 388 accounts: 175 production activities, 139 retail commodities, one trade margin account, 43 factor types, one enterprise account, 19 household accounts, seven government accounts (including six tax accounts), one savings-investment account, one stock changes accounts, and one 'rest of the world' account. Subsequently, the number of activities and commodities were reduced to 10 each, in order to reduce the complexity of the model and facilitate numerical computation: agriculture, industry, utilities, housing and infrastructure, transportation, trade, public administration, health, education, other services. (This breakdown of activities and commodities were considered to be a reasonable trade-off between reducing computational complexity and maintaining sufficient sector detail in order to allow for modelling of domestic trade as well as health- and skill-consequences of malaria). 
Type Of Material Database/Collection of data 
Provided To Others? No  
Impact This Social Accounting Matrix is for use with the integrated model. Impacts from this item result from the combined use of our model framework with this dataset rather than from the Social Accounting Matrix by itself. 
 
Title Tanzania Districts 2009 Shapefile 
Description It appears that GIS shapefiles for Tanzanian district borders exist for 2002 but not for the time period proposed for our integrated Tanzania model (2009). For this reason, an ARCGIS shapefile for the 2009 district borders of Tanzania has been constructed as a means to parameterise the malaria model component of our Tanzania integrated framework. 
Type Of Material Database/Collection of data 
Provided To Others? No  
Impact This shapefile was used facilitate the construction of a consistent database to underly our Tanzania integrated framework. 
 
Description Conference Poster and Presentation (ASTMH) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Poster was available during conference schedule. Additional verbal presentation and discussion of the poster was made at the scheduled time.

Increased awareness of the value of the macroeconomic/integrated modelling approach.
Year(s) Of Engagement Activity 2013
 
Description Conference Presentation (Malaria Retreat 2013) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Further interest was sparked in our integrated modelling methodology.

After the presentation several researchers discussed the specific application and macroeconomic modelling of health more generally with the presenter.
Year(s) Of Engagement Activity 2013
 
Description Conference presentation (GTAP 2013) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other academic audiences (collaborators, peers etc.)
Results and Impact Premier event for CGE modelling - 16th Annual Conference on Global Economic Analysis, Shanghai, China, June 12-14, 2013

The presentation provoked discussion both during and following the scheduled talk. It also provided an important opportunity to highlight advances in health-related applications to the macroeconomic modelling community.
Year(s) Of Engagement Activity 2013
 
Description Conference presentation (HESG 2014) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Other academic audiences (collaborators, peers etc.)
Results and Impact Premier event for health economics in UK - Health Economics Study Group, Sheffield, 8-10 Jan 2014

This presentation sparked considerable discussion and was important in highlighting the value of the macroeconomic approach to the health economics community.
Year(s) Of Engagement Activity 2014
 
Description Conference presentation (Malaria Retreat 2011) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Type Of Presentation paper presentation
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact The presentation was awarded the prize for best presentation over the two day conference. Considerable interest in the work followed by conference participants.

Following this presentation, collaboration with the Malaria Atlas Project ensued which resulted in obtaining valuable data for model parameterisation.
Year(s) Of Engagement Activity 2011
 
Description Ghana Validation Workshop 2013 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Other academic audiences (collaborators, peers etc.)
Results and Impact Dr. Philomena Nyarko, Acting Government Statistician and Chief Executive of the Ghana Statistical Service invited Marcus Keogh-Brown and Henning Tarp Jensen to a validation workshop at the School of Public Health, University of Ghana, Legon. The malaria focussed CGE model of Ghana was presented to an audience of more than 200 faculty members and members of the Ghana Statistical Service for comments and to elicit suggestions for improvement to the methodology and scenario design.

This meeting drew a large Ghanain audience to comment on the methodological framework developed for Ghana. The meeting served to strengthen the researchers contacts in both Ghanaian Statistical services and academia.
Year(s) Of Engagement Activity 2013
 
Description Ghana Visit and Participation in African Statistics Day Conference 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? Yes
Geographic Reach National
Primary Audience Policymakers/politicians
Results and Impact Marcus Keogh-Brown and Henning Tarp Jensen attended this event and gave a presentation on 20th November.

This presentation was followed by a personal meeting with Ghana's Acting Government Statistician (now Government Statistician), Dr. Philomena Efua Nyarko who takes a continuing interest in our work.
Year(s) Of Engagement Activity 2012
 
Description Malaria Eradication Strategic Advisory Group, Economics Work Stream 13 - 15 June 2017 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact The objectives of the meeting were to:
• Review the overall conceptual framework for addressing economic issues relevant to malaria eradication;
• Review proposed plans to estimate the microeconomic impact of malaria control, elimination & eradication (estimating the costs of malaria programme expansion and the impact on health service costs, household costs and production);
• Review proposed plans to estimate the macroeconomic impact of malaria control, (including assessing the impact of economic development on malaria);
• Review malaria financing trends & the potential for programme expansion or efficiency gains;
• Agree on roles and responsibilities and next steps forward;
• 2016, including country and regional profiles as well as the core content of the website to be launched in parallel with the report release.
Approximately 25 people participated, our integrated malaria modelling framework was presented and a report of the meeting was produced.
Year(s) Of Engagement Activity 2017