The macro-economic determinants of health and health inequalities—umbrella review protocol
Naik et al. Systematic Reviews
The macro-economic determinants of health and health inequalities-umbrella review protocol
Yannish Naik 0 1 2
Peter Baker 0 3
Ian Walker 7
Taavi Tillmann 6
Kristin Bash 2
Darryl Quantz 5
Frances Hillier-Brown 4
Clare Bambra 8
0 Equal contributors
1 Leeds Institute of Health Sciences (LIHS) , Level 10, Worsley Building, Clarendon Way, Leeds LS2 9NL , UK
2 Leeds Teaching Hospitals NHS Trust , Leeds , UK
3 Imperial College London , London , UK
4 Institute for Health & Society, University of Newcastle , Newcastle upon Tyne , UK
5 University of Lancaster , Lancaster , UK
6 University College London , London , UK
7 Nuffield Centre for International Health and Development, University of Leeds , Leeds , UK
8 Newcastle University , Newcastle upon Tyne , UK
Background: The economic determinants of health have been widely recognised as crucial factors affecting health; however, to date, no comprehensive review has been undertaken to summarise these factors and the ways in which they can influence health. We conceptualise the economy as a complex system made up of underlying approaches, regulation from institutions, markets, finance, labour, the public-private balance as well as production and distributional effects, which collectively impact on health through the effect of moderators. This protocol details the methods for an umbrella review to explore the macro-economic factors, strategies, policies and interventions that affect health outcomes and health inequalities. Methods: We will identify relevant systematic reviews using search terms derived from the Journal of Economic Literature classification. Reviews will be included if they meet the Database of Abstracts and Reviews of Effects criteria for systematic reviews. Reviews of studies with and without controls will be included; both association and intervention studies will be included. Primary outcomes will include but are not limited to morbidity, mortality, prevalence and incidence of conditions and life expectancy. Secondary outcomes will include health inequalities by gender, ethnicity or socio-economic status. Six databases will be searched using tailored versions of our piloted search strategy to locate relevant reviews. Data will be extracted using a standardized pro forma, and the findings will be synthesized into a conceptual framework to address our review aim. Discussion: Our umbrella review protocol provides a robust method to systematically appraise the evidence in this field, using new conceptual models derived specifically to address the study question. This will yield important information for policymakers, practitioners and researchers at the local, national and international level. It will also help set the future research agenda in this field and guide the development of interventions. Systematic review registration: This umbrella review protocol has been registered with PROSPERO CRD42017068357.
Economics; Socio-economic determinants; Trade; Finance; Labour; Public-private; Market; Regulation; Production; Distribution
There has been long-standing recognition of the
role of economic factors on health and well-being
]. These economic factors are consistently
identified in local, national and international population
health frameworks as both influences on health
and levers to improve health and reduce health
inequalities. Building on these frameworks, there
have been several efforts to quantify the impact of
the social determinants relative to other influences
such as healthcare services. In line with ongoing
advocacy for investment in the wider determinants,
the results indicate that social and economic
factors are the largest influences on population health
]. In spite of this evidence and formal calls for
action dating back to the Ottawa Charter, there
continues to be frustration over the lack of
practical policy interventions around social and
economic determinants .
This lack of action has been attributed to the
challenge of understanding the multifaceted impacts
of social and economic factors, as well as the need
for long-term outlooks to address policy problems
]. This is particularly pertinent in light of policy
debates around Health in All Policies—a move to
consider the impact on health and health
inequalities in all aspects of government policy . In
response, there are calls to consider economic policies
as health policies with research and evaluation that
would more clearly identify the mechanisms through
which economic factors/policies affect health [
Berkman notes that ‘understanding the ways in
which social and economic policies impact
population health is one of the most critical areas for
public health today’ [
To date, public health researchers have begun to map
out the interconnected pathways and linkages between
economic conditions/policies and health outcomes. For
example, the links between poverty and poor health are
wide-ranging and well-documented with lower income
being associated with both behavioural risk factors, such
as smoking, and a range of negative health outcomes
]. Similarly, involuntary unemployment and its
related income loss are associated with negative health
More recently, there is growing media and public
awareness over income inequalities which have
continued to grow amongst OECD (Organization for
Economic Co-operation and Development) countries
over the last 30 years in spite of significant periods of
economic growth [
]. Wilkinson and Pickett have
highlighted the body of evidence which shows the
impact of income inequalities on a range of population
health and social outcomes . Recent research has also
highlighted a potential link between ‘neo-liberal’ economic
policies such as reductions in public sector spending and
increased stress, obesity and health inequalities [
These growing income and wealth gaps, combined with
environmental concerns, have instigated debate and
proposals for alternative economic systems that could
deliver improved health outcomes and reduced health
12, 15, 17
Seminal social determinants reviews and
commissions have begun to specify economic policies
within recommendations frameworks. The 2008
World Health Organisation Commission on Social
Determinants of Health (SDH) [
] listed a few of
these elements, such as ‘social protection’,
‘progressive taxation’, ‘debt relief ’ and ‘market responsibility’.
This was further developed by the European review
of SDH [
], which also looked at ‘gross domestic
product (GDP), taxation and welfare’ and
‘economics’. These prominent reports have drawn upon the
wide literature of associations between health and,
as Dahlgren and Whitehead [
] described it, the
general socio-economic, cultural and environmental
conditions in society, and also began the process of
formalizing these into core themes and categories.
The overall pattern is one where purely economic
determinants are frequently conceptualized
alongside other wider determinants of health (such as
environmental and political determinants). This
frame might have been too broad, thereby
preventing the formation of a comprehensively structured
schema of the Economic Determinants of Health.
On the other hand, we recognize recent work to
define narrower constructs, such as the commercial
determinants of health [
]. In our view, these
could nonetheless be nested with a wider framework
of Economic Determinants of Health, which we
hope our review could inform.
The literature has now gone beyond investigating
the determinants to identifying potential
interventions. Khan et al. carried out a rapid scoping review
] and found 195 systematic reviews of economic
interventions. They found that taxes and subsidies
could be used to encourage use of services and
healthy patterns of consumption, income transfer
programs can support individuals to meet their
needs and encourage treatment adherence and that
incentives can be used to alter provider and patient
behavior. They also found that livelihood support
programs can help to increase income, through
supporting people to earn a higher income for
example. Finally, they found that health-related
financial services such as insurance could help
householders to manage healthcare-related financial
risk. However, we suggest that their definition of
economic interventions is limited, ignoring, for
example, macro-economic interventions such as
fiscal policy and trade policy. Despite progress to date,
no comprehensive overview of the macro-economic
determinants of health, their relative importance
and the different mechanisms through which they
affect health has been produced.
We thus aim to carry out a review to provide a
rigorous evidence base around the macro-economic
determinants of health and health inequalities. We aim to
provide a conceptual model to understand the links
between the economy and health and use this
conceptual model to explore the existing evidence base
systematically. We will thus provide evidence to policymakers,
researchers and health advocates which can be used to
develop evidence-based economic policy interventions
and clarify priorities for further research. Given the
broad scope of this research question and the large
number of existing systematic reviews on each of its
subtopics, we aim to carry out an umbrella review—a
methodology which involves carrying out a systematic
review of reviews [
The economy has been defined as a ‘social domain that
emphasizes the practices, discourses, and material
expressions associated with the production, use and
management of resources.’ [
]. The economy is thus
conceived of as a complex interacting system which
influences health through a number of mediators (access
to healthcare, housing, etc.).
The Journal of Economic Literature (JEL) provides
a classification [
] of the key concepts that relate to
research in economics. Based on the JEL terms and
our conceptual framework, we propose that the
economic factors that influence health can broadly be
conceived of in seven major categories—market
regulation; institutions; supply of money; finance and
loans; the balance between the public, private and
third sector; labour; production and consumption
and approaches to the economy. Table 1 presents
these seven categories, related subtopics for each
Some factors could be in multiple categories. They have been assigned to the most relevant category
e.g. International Monetary
Fund, World Bank,
multinational firms, World
International lending, foreign Financial crises and suicide rates [
aid, financial transactions tax,
Illustrative example of impact
on health (if known)
Regulation of the tobacco market, via
taxation and restrictions on
advertisement and right to trade with
tobacco has been associated with a
range of benefits such as reduced
heart disease [
Loans issued by the IMF and subsequent
tuberculosis mortality [
Mass privatization and mortality in the
former Soviet Union [
Unemployment and suicide [
Overwork and stroke [
Income inequality and mortality [
Political traditions more committed to
redistributive economic policies may
lead to improvements in the health of
Category 1: market
Category 3: supply
of money, finance
Category 4: balance
private and third
Category 5: labour
Competition including legislation,
consideration of externalities in
pricing, fiscal measures, e.g. tax,
Central bank, banks, micro-finance,
mortgages, startups. Legislation and
regulation of organisations
Interest rates, inflation, deflation,
wages, supply of money or credit,
macro-economic policy, fiscal policy,
financial crises, monetary policy,
structural adjustment policies, natural
Structure and scope of government,
privatization and nationalization,
taxation, tax avoidance, government
expenditure and welfare provision,
category at the local, national and international level
as well as illustrative examples of potential health
implications. Whilst we acknowledge that this list is
not exhaustive, it provides an initial framework to
guide our search strategy. We also propose an a
priori simplified framework (Fig. 1) to show the
broad relationships between economic factors and
health that we are investigating.
We used the Preferred Reporting Items for Systematic
review and Meta-Analysis Protocols (PRISMA-P) checklist
] to develop this umbrella review (see Additional file 1
for the completed checklist).
What are the macro-economic factors, strategies,
policies and interventions that affect health outcomes
and health inequalities?
The umbrella review method provides a transparent
and rigorous approach to reviewing the highest
quality evidence on a broad topic and is increasingly
common in the field of public health [
protocol for this systematic review is registered on
PROSPERO (CRD42017068357), and any
amendments will also be registered.
Two restrictions of our scope are important to state.
Firstly, the economy is usually analyzed on two
levels: the micro level—concerned with economic
decision-making at the individual and household
level—and the macro level—concerned with
largescale aspects such as the size of the economy,
monetary policy, labour policy and trade. This review
will focus on population-level macro-economic
determinants and associated health outcomes, because
there has already been substantial work on
microeconomics and health [
]. However, we recognize
that these distinctions may be contentious, and thus
we have had to use our judgment to draw pragmatic
boundaries around the scope of the study.
Secondly, economic factors impact on health partly
through mediators such as healthcare expenditure,
other social determinants of health such as housing
and environmental factors such as pollution and
climate change. Each of these mediators is likely to
involve a complex causal chain with a significant
evidence base around its health impacts. It is not
practically possible to review the impact of the
economy on each of these mediators or the impact of
each of these mediators on health as each of these
would likely require a separate systematic review. We
will thus not include these mediators within our
review. Instead, we will focus on reviewing the overall
association between economic factors and health. The
inclusion criteria for our review of systematic reviews
are listed in Table 2.
We will search Medline (Ovid), Embase (Ovid),
Econlit (EBSCO), PsycInfo (Ovid), Applied Social
Sciences Index and Abstracts (ASSIA; ProQuest)
and Sociological Abstracts (ProQuest) for relevant
Table 2 Criteria for including systematic review articles, in the present umbrella review
Study design Systematic reviews meeting Database of Abstracts of Reviews of Effects (DARE) [
] criteria: (i) a defined review question
(which includes at least two out of population, intervention, comparison, outcomes or study designs), and with a search
strategy of a named database, and (ii) a search strategy including both a named database (at least) and one of the
following: reference checking, hand searching, citation searching or contact with authors.
These reviews can include observational and experimental studies—for example randomised and non-randomised studies,
cohort studies, intervention studies and cross-sectional association studies, as well as effectiveness, cost-effectiveness,
modelling and implementation studies.
No restriction based on the length of follow-up of outcomes.
Adults and children in high-, low- and middle-income countries.
The reviews must primarily focus on macro-, population-level rather than individual-level economic determinants of health.
This may include reviews of association and modelling studies as well as reviews of intervention studies.
Systematic reviews of studies with and without controls will be included
Health and health inequality outcomes. Primary outcomes including but not limited to morbidity, mortality, prevalence
and incidence of conditions and life expectancy. Secondary outcomes include health inequalities by gender, ethnicity or
socio-economic status (for example by income, education, employment, receipt of benefits at an individual or area level).
Cost-effectiveness data will also be extracted if available.
Any setting—low, middle, high-income countries.
All years since the start of database.
Only peer-reviewed published studies
papers, developing tailored searches for each
database. This will ensure we will synthesize the
best evidence from all the relevant disciplines. We
will hand-search key reviews for further citations.
We will only include peer-reviewed published studies
and so will exclude grey literature to ensure the highest
quality of evidence is reported.
Screening, data extraction and quality appraisal
Core members of the review team will screen the titles
and abstracts to exclude irrelevant papers, with a second
author screening a random 10% sample [
]. A lead
author will act as arbitrator in case of disagreement.
Two authors will independently review the full text of
articles to determine inclusion, discussing any
disagreement and, if need be, discussing this with a third author
also. We will calculate the percentage agreement
between reviewers at the title and abstract screening
stage and for full-text inclusion.
We will extract key data from full-text versions of
included papers using standard extraction forms adapted
from previous reviews for this purpose [
Table 3 for key data points to be extracted). We will
then quality appraise the reviews selected using the
Assessment of Multiple Systematic Reviews (AMSTAR)
approach  as part of our standard extraction form.
This approach explores for example study selection and
extraction, search details, methods of synthesis,
assessment of publication bias and conflict of interest. It is
now widely accepted as part of umbrella review
methodology being easy to use and having been externally
Where a meta-analysis has been carried out, we will
report the combined effect size. Where the review does
not provide a summary measure of effect, we will
explore the key findings and use these to inform a
narrative overview of the key findings. We will also
discuss the methodological weaknesses of the studies
underlying them [
] and offer recommendations on
future study designs. We do not plan to carry out
meta-analysis given the broad topic being studied.
Through this synthesis, we aim to summarise the
latest evidence in this field and develop a conceptual
framework that will provide insight into the different
subtopics under study. The findings of our review
could be applied as recommendations for practice for a
range of stakeholders, as well as helping to identify major
gaps in the evidence to set future research agendas.
Pilot search strategy
We developed an ‘economic’ search strategy from
the American Journal of Economic Literature (JEL)
classification system [
] which is used to categorise
economic literature (see Additional file 2 for JEL
terms that were included and excluded). We
included JEL terms focused on the economy or its key
components or policies (see Table 1) and excluded
JEL categories that were purely theoretical or
methodological, or that were focused on the micro level
(individual or household).
We then developed a ‘health outcomes’ search based
on key concepts which might be associated with the
economic terms we chose, and on a previously used
]. In line with this previous umbrella
review, we decided not to include specific inequality
terms as these might excessively restrict our search
results. We modified the Scottish Intercollegiate
Guidelines Network (SIGN) terms to limit our search
to systematic reviews [
], ensuring the search was
more specific than previously used searches [
We refined search terms through consultation with
topic experts and information specialists. We further
developed the searches through an iterative process,
including Medical Subject Headings (MeSH terms) as
]. This involved a number of pilot
searches followed by a discussion of possible
amendments to our strategy at each stage and refinement.
Given the breadth of the review, it was important to
balance the sensitivity and specificity of our search
strategy. To do this, we identified terms that might have
ambiguous health and economic concepts (e.g. deprivation)
which would have reduced the specificity. We
respecified or removed them as appropriate to ensure the
search remained focused. We developed a pilot search
strategy for Medline (see Table 4 for number of results).
We tested the sensitivity of the pilot search strategy by
checking the inclusion of key ‘tracer papers’—these are
papers we would expect our search to find, in line with
previous umbrella reviews [
] (see Table 4). All
tracer papers were picked up by the pilot search;
therefore, the search strategy was finalised for Medline
(Additional file 3) and will be adapted for other databases.
This umbrella review will provide, for the first time,
a systematic overview of economic determinants of
health. It will offer a broad overview of existing
evidence and identify key gaps in the current
knowledge. We will seek to use the results in a novel
conceptual framework which will assist in bringing
together the diverse disciplines that inform this field.
This can be used to inform international, national
and local policy to improve health. Understanding
the impact that macro-economic determinants have
on health, and gaps in this evidence, will also help
set the future research agenda in this field and guide
the development of interventions. Building on
previous reviews, we will also discuss the impact of
context on the economic determinants of health [
given the increasing recognition of the importance of
contextual factors in public health [
Additional file 1: PRISMA-P checklist. (DOC 84 kb)
Additional file 2: AEA JEL codes for inclusion. (DOCX 85 kb)
Additional file 3: Search strategy for Medline. (DOCX 94 kb)
AMSTAR: Assessing the Methodological Quality of Systematic Reviews;
DARE: Database of Abstracts and Reviews of Effects; GDP: Gross domestic
product; JEL: Journal of Economic Literature; MeSH: Medical Subject
Headings; OECD: Organization for Economic Co-operation and Development;
PRISMA-P: Preferred Reporting Items for Systematic review and Meta-Analysis
Protocols; PROSPERO: International Prospective Register of Systematic
Reviews; SDH: Social determinants of health; SIGN: Scottish Intercollegiate
We would like to thank Aaron Reeves, Daniel O’Neill, Malcolm Sawyer, Lukas
Bunse, Peter Roderick, Reinhard Huss and Rocio Rodriguez Lopez for their
helpful comments on earlier versions of this protocol.
Salaries were paid by respective employers. TT is funded by a Wellcome
Trust Fellowship [106554/Z/14/Z]. CB is an associate director of Fuse, the
Centre for Translational Research in Public Health. Funding for CB and Fuse
comes from the British Heart Foundation, Cancer Research UK, Economic
and Social Research Council, Medical Research Council and the National
Institute for Health Research, under the auspices of the UK Clinical Research
Collaboration, and the funding is gratefully acknowledged. The views expressed
in this paper do not necessarily represent those of the funders or UKCRC. The
funders had no role in the study design, data collection and analysis,
decision to publish or preparation of the manuscript. CB Fuse Grant
Availability of data and materials
YN and PB are joint first authors. YN, PB and CB identified the topic and led
the design and development of the protocol. YN and PB drafted the manuscript
and TT, IW, KB, FHB, CB and DQ contributed to the development of methods and
revision of the manuscript. All authors read and approved the final manuscript.
Ethics approval and consent to participate
Consent for publication
The authors declare that they have no competing interests.
Springer Nature remains neutral with regard to jurisdictional claims in
published maps and institutional affiliations.
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