Background

This paper relates the protocol of the GoveRnance for Equity, EnviroNment and Health in the City (GREENH-City) project funded by the French National Institute for Cancer (INCa – N°RI-2017-003). This research aims to identify the most promising interventions to operationalize the approaches of Health in All Policies at the city level to tackle health inequities through urban green spaces. Figure 1 presents the rationale and the objectives of the project.

Fig. 1
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Rationale, research setting, objectives and methodological approach of the GREENH-city project

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Health inequities are much larger in France than in most other European countries even though its health system was considered in the early 2000s as one of the best in the world. Today it ranks 15th on a world scale [1]. Health inequities arise from a multitude of health determinants which go beyond health systems themselves. As noticed by the Marmot commission, these inequities are “seen in the conditions of early childhood and schooling, the nature of employment and working conditions, the physical form of the built environment, and the quality of the natural environment in which people reside. Depending on the nature of these environments, different groups will have different experiences of material conditions, psychosocial support, and behavioural options, which make them more or less vulnerable to poor health” [2] .

Numerous studies exist today showing the influence of social, economic, geographic or political factors across the life course as determinants of health [3,4,5,6,7]. These determinants affect individuals unevenly and thus create health inequities [8].

The effect of environmental factors

Early research into health determinants often dealt with health behaviors (eating habits, alcohol consumption, smoking, sports etc.) and their link with non-communicable diseases including cancer. More recently, research has started looking into other health determinants and the role of environmental factors such as exposure to air pollution and heavy metals.

Environmental determinants are not necessarily risk factors; they may also offer health benefits [9]. For example some studies have shown that green urban spaces support health living for city dwellers [10,11,12,13,14].

Green spaces in the built environment

As urban environments expand, new health challenges arise for the population living in them [15]. In this respect urban green spaces can help improve living conditions and influence people’s health and wellbeing [16,17,18,19,20]. The proximity and access to green space offers both physical and mental health benefits. A recent WHO review has shown for example that immune systems may be enhanced by the relaxation provided in green spaces [14]. Green spaces act on cognitive functions and mental health. They also have an impact on chronic diseases such as type 2 diabetes, hypertension, cardiovascular disease and certain cancers [10, 12, 21].

Furthermore, urban green spaces encourage healthier behaviors such as physical activities. They also provide recreational settings and promote social cohesion [22]. Lastly, their features, type and size all contribute to regulating urban ecosystems by depolluting the air, and reducing noise levels and the heat island effect [23].

Some studies have shown that health benefits provided by green spaces affect individuals to varying degrees according to age, gender, physical condition and social position [24, 25]. For example, these effects are thought to be greater on people belonging to lower social categories. The reason for this may relate to higher levels of physical, mental and social vulnerability than in upper social categories, or differences in exposure to the characteristics of green spaces: physical features which are either salutogenic (protective exposure) or pathogenic (exposure to harmful substances or air pollution) [13].

Green space management policies

Some green space management policies can be detrimental to health. This includes the use of phytotoxic products, pesticides and herbicides which also has an adverse effect on biodiversity [11, 17].

However other policies have adopted a more sustainable approach to managing their green spaces. Such approaches can offer positive health outcomes through the mechanisms described above [11, 16, 24, 26, 27].

To understand how urban green spaces affect people’s health, we need to study their accessibility, management and features at the same time. There is, however, great variability in public policy across cities and districts, which leads to different levels of green space access and thus to health inequities [28, 29]. There are many definitions of urban green space in the literature which may or may not include: public parks, closed public green spaces (school playgrounds etc.), private gardens, blue spaces, play areas, allotments [14]. All may have some effect on people’s health.

Urban green spaces and health: Where health in all policies (HiAP) come into play

New forms of policy engagement need to be introduced if health issues are to be addressed by sectors that traditionally are not directly concerned with health, such as environmental planning and green spaces.

In this respect, the HiAP approach offers a promising framework [30,31,32,33] for integrating health into other areas of policy as a way to support the wellbeing of the population and to achieve equity in health [34,35,36,37]. HiAP is important for acting on the social and environmental determinants that affect people’s living conditions and health inequities [38]. The most appropriate level at which to implement this approach would seem to be the local level [39]. In France, urban green space policies and management are principally the responsibility of towns and cities councils. Although there is an increasing amount of international research into urban green spaces and their effects on health, little research has been conducted on the policy choices made by cities with regard to green space management and their potential impact on health inequities.

The research protocol of the GREENH-City project therefore explores a relatively new area. The setting of the research is based in the French WHO Healthy Cities Network, whose members are committed to implementing HiAP to address health inequities and urbanism.

Research questions and objectives

Considering this background, the project seeks to answer the following questions: what policies are French cities developing with regard to green spaces and health? How do these policies address health inequities and HiAP? What are the contexts and the right conditions for rolling out these policies at a local level? How does the population use or not use these urban green spaces? Does the whole population have access to these urban green spaces and in what conditions? And lastly, to what extent do these contexts and policies enable health inequities to be tackled?

Using mixed methods, this study explores the policy making processes which are favorable to health and the links with green space policy and health inequities. Bauman’s framework (2014) serves as a general framework to identify the HiAP process and the cities’ involvement in green space policy [40]. Within this framework, different levels of the HiAP approach can be analyzed: policy design, policies developed and synergies identified, relevant policies implemented, indicators of success, population outcomes. As such, the research objectives are to:

  • understand how the cities implement HiAP in order to take into account the health inequities thanks to the political decisions related to green spaces (Objective 1)

  • describe and analyze the interventions produced and implemented within the cities on the green spaces from a geographical point of view, according to the socio-economic characteristics of cities and neighborhoods (Objective 2)

  • analyze the use and the contribution of urban green spaces to health and well-being of the inhabitants (Objective 3).

This study explores how public policy is actually implemented in the cities of the French WHO Healthy Cities Network. It is a real life interventional study in which various situations will be compared and contrasted to identify the best configurations for addressing health inequities in developing or maintaining urban green spaces.

The PRISMA-P 2015 checklist items relevant for this type of study are used to present this protocol.

Methods/design

The project will be implemented by a multidisciplinary team: political sciences, social geography, urban planning and public health. Different institutions and stakeholders are involved in the project: researchers from two universities EHESP-School of Public Health and University of Paris Nanterre, practitioners from the WHO French Healthy Cities Network and experts with experience in HiAP (Institute of Global Health of Geneva University and École supérieure d’aménagement du territoire et de développement régional de l’Université Laval).

Setting of the research

In France, cities are legally responsible for organization of public services such as crèches and retired people’s homes, transport, spatial planning and local development, which may strongly impact the urban environment. Health policies come mainly under the jurisdiction of other institutions (National and regional health authority authorities). Some cities choose, for historical reasons, or by political will, to actively promote health issues in addition to their legal mandates.

Study design

This mixed-method research combines a large quantitative study alongside in-depth qualitative case studies [41] (See Fig. 2).

Fig. 2
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Mixed methods methodological approach: data collection, analysis and interpretation procedures and products (QUAN = quantitative; QUAL = qualitative)

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The case study design is used because we seek to understand the contextual conditions which we think will influence the phenomena studied. By combining multiple data sets, it should provide complete and in-depth picture of the phenomena [42].

The sample

This research will based on city members of the French WHO Healthy Cities Network, set up on the initiative of the WHO Regional Office for Europe. The French Healthy Cities Network, which is one of the most developed and structured networks in Europe, has been chosen as a sample for this study as it covers health issues across various fields, policies and programs conducted by the city members. The members of the French Healthy Cities network take a keen interest in health and health inequities. As such, they can provide a setting for research to identify policy action in health that is conducive to reducing health inequities. The Network has to develop HiAP at a local level. These principles were recently reaffirmed by the Declaration of [43] which strengthens the leadership of cities in promoting health and wellbeing and in tackling inequities. Adhering to the Athens Declaration represents a strong political statement and all network members agree to uphold it. Therefore, this network has been identified as being most suitable for the purposes of our study since member cities and conurbations do, theoretically, implement HiAP already.

First of all, a large quantitative study will be conducted across the 80 city members. These cities are considerably varied in terms of their populations, their political orientation (right wing/left wing) and urban configuration (from 6000 to over 2 million inhabitants). Among the 80 members, a sub-sample of 6 cities will be identified for an in-depth comparative study.

Research proceedings

The project has been divided into work packages which can be undertaken concomitantly:

  • Work package A involves a baseline study to analyze the characteristics of the Healthy Cities Network.

  • Work package B investigates objective 1: Understand how cities implement the approach of health in all the policies, in order to take into account the health inequities thanks to the political decisions related to green spaces,

  • Work package C investigates objectives 2 and 3: Describe and analyze cities’ interventions produced and implemented on the green spaces from a geographical point of view, according to the socio-economic characteristics of the cities and neighborhoods and analyze the use and the contribution of urban green spaces to health and well-being of the inhabitants.

  • Work package D involves cross-analysis of data and proposed recommendations.

More details about the work packages are provided below including their aims, the dimensions studied and the theoretical frameworks underlying the methods used. A table of the workpackages explaining for each one of them the objectives, method, population, analyzed dimensions, tools and deliverables is presented in Annex 1 (See Additional file 1 presenting Objectives and Methods by Workpage).

  • Work package A (QUANT): Baseline study: Healthy Cities network characteristics (N = 80 cities)

A large quantitative study (see Table 1) will be done across the 80 city members of the French WHO Healthy Cities Network. A database will be developed. This database will be used to select 6 city cases (first step in Work package B). Furthermore, drawing on the data from the 80 cities, city profiles will be identified and will contribute to the transferability of results (Work package D).

  • Work package B (QUAL-quant): Characterization of the HiAP approach and governance and green space policies (N = 6)

Table 1 Goals, dimensions, methods and tools for work package A
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In order to develop the case studies, the aim is to select 6 city profiles based on socio-economic and urban green spaces characterization and a typology regarding the HIAP process in the cities and the inclusion of health into green spaces policy. This approach is based on the assumption that in cities with equivalent socio-economic characteristics, the maturity level of the HiAP process determines equity and health in green space management policy.

Two levels will used to select cities included in the in-depth study according to the city’s administrative organization, the response to the HiAP survey, the socio-economic heterogeneity and degree of spatial fragmentation, asynthetic indicator of urban green space availability and the maturity of the HiAP process. The selection levels are described in Fig. 3.

Fig. 3
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Selection levels to identify cities includes in the in depth study. *UGS: Urban green space. *MCDM: multiple criteria decision making

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The sample of cities will present the 6 different profiles. Should these two levels of selection happen to be insufficient for selecting 6 city cases, we will apply a multiple-criteria decision-making approach using preference criteria based on the ELECTRE and PROMETHEE methods [44]. The Advisory Board will determine the number and nature of the criteria to put into the preference model.

Once the 6 cities are identified, the qualitative in-depth study for each city will be developed as presented in Table 2.

  • Work package C (QUAL - QUANT) – Geographical characterization of green spaces and green spaces use (N = 6)

Table 2 Goals, dimensions, methods and tools for work package B
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In order to characterize the green spaces and their use in each one of the cities, the in-depth study of the cities will be completed with this workpackage. The aims, dimensions and methods are presented in Tables 3 and 4.

  • Work package D: Case study synthesis and transferability

Table 3 Goals, dimensions, methods and tools for work package C1
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Table 4 Goals, dimensions, methods and tools for work package C2
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The collection of cases will be cross-analyzed (WP D1). Each case study will deliver:

  1. 1.

    a typology of cities regarding their local political system and HiAP governance concerning green spaces and health inequities (results of the socio-political analysis) which will be crossed with the distribution of green spaces across the city (results of the spatial analysis). This typology will help to identify different city profiles

  2. 2.

    a typology of green spaces for each city regarding their locations, representations, uses, amenities (i.e. defined criteria during the study) which will be crossed with the level of use of green spaces.

In order to answer our main research question, those two types of typologies will be crossed to identify:

  • for similar “green space” types and urban context but different “modes of governance”, which mode of governance seems to favor wellbeing and tackle the health inequities

  • for similar “modes of governance” but different “green space” types and urban context, which configuration of green spaces seems to favor wellbeing and tackle health inequities.

The aim is to set out contextualized recommendations for all the network cities, based on the lessons from the 6 cases (WP D2).

We will first establish the profiles of the 80 cities according to 4 dimensions:

  • Contextual factors: socio-demographic situation and dynamics, position of the city in the French Healthy Cities Network, location of the city in relation to important or significant natural places such as mountains, sea, and preserved national parks,

  • socio-economic characteristics: the socio-economic heterogeneity and urban segregation,

  • the HiAP approach’s degree of maturity,

  • green space characteristics: size, nature, context and accessibility.

Secondly, we will compare the profiles identified with the components of HiAP governance suited to implementing green spaces in urban areas. For each profile we will identify the strengths and weaknesses with regard to HiAP governance for implementing green spaces suited to healthy living and for setting out contextualized guidelines for each case.

A methodology will be developed from this and disseminated widely. It will be sent to cities (including those outside the WHO network) to enable them to analyze their own possibilities for HiAP governance applied to green spaces in urban areas. The project includes various knowledge transfer modalities such as: the production of policy-briefs, local seminars and a national conference with local politicians and other policy makers. A collective publication similar to other produced by the WHO Healthy Cities Network [45] containing the most promising interventions will be part of the sharing of key messages at both local and national level. Tables 5 and 6 present the knowledge transfer strategic plan.

Table 5 Knowledge transfer strategic plan (part 1)
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Table 6 Knowledge transfer strategic plan (part 2)
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Discussion

This study protocol is designed to explore Health in All Policies (HiAP) as a way to help reduce health inequities through the use of urban green spaces. The research aims to produce a set of guidelines based on good practice at local and municipal level. However it is highly important for results to be replicable and for practitioners to adopt the new-found knowledge. This is challenging as results need to fit local contexts and be accepted by stakeholders. If public policy makers are to adopt these guidelines, they need to understand what they are for and how they can implement them within their own local contexts and practices. Transferring and applying results therefore means addressing contextual factors and understanding the constraints under which policy makers have to operate. One way to achieve this is to implement an approach that is both interventional and participative.

The GREENH-City project design comes under real life studies. There are recommended as a way of understanding the impact of population-level policies on health outcomes or health inequities [46, 47]. They differ from controlled experiments in that researchers do not manipulate any intervention data, but only observe them in real-life conditions. They involve a comprehensive approach to processes, which lends itself particularly well to observing policy processes [48, 49]. The research design is suited to studying municipal policy making and governance relating to health and green spaces, which is what we are looking to study. In this research therefore, the factors observed in-situ will be contextual factors specific to each case.

This approach enables us to identify, according to context, how a policy may have a bearing on health inequities. Contexts are an integral part of the analysis and they define the key elements for ensuring a replicable methodology. They enable us to understand the extent of health outcomes achieved by HiAP processes, and they act as policy levers to improve practices. By understanding what is replicable in another setting, we can adapt our guidelines and help ensure HiAP in urban areas can be applied to green spaces in new contexts.

GREENH-City is also about participative research in that it involves project beneficiaries (WHO Healthy Cities Network member cities) throughout. The cities involved are both areas of exploration and research partners. The participatory process is important to secure results appropriation and to improve their transferability. The French Healthy Cities Network will continue to engage with stakeholders in order to help ensure practical uptake of the results. Stakeholder involvement in the intervention design and implementation relating to green spaces is certainly a success factor for the interventions [50].

Conclusion

This study covers a new area of research relating to urban policy on green spaces and its influence on social and territorial inequalities in health. The aim is to help improve people’s health and to act on those factors which influence chronic disease positively or negatively through living conditions. The study considers how the built environment may offer greater health outcomes and how green spaces are essential to wellbeing. This interventional research will be applied locally using a participative approach. It has a natural experiment design, addressing the specific contexts of each case study. A set of guidelines will be produced from this study so that other cities may enhance their green space policies and reduce health inequities.