==== Front BMC Public Health BMC Public Health BMC Public Health 1471-2458 BioMed Central London 15908 10.1186/s12889-023-15908-0 Research Article Healthy city: global systematic scoping review of city initiatives to improve health with policy recommendations http://orcid.org/0000-0002-7739-9529 Danielli Shaun Shaun.danielli@kcl.ac.uk 12 Ashrafian Hutan 2 Darzi Ara 2 1 grid.239826.4 0000 0004 0391 895X Kings Health Partners, Guys Hospital, London, SE1 9RT UK 2 grid.7445.2 0000 0001 2113 8111 Imperial College London, South Kensington Campus, London, SW7 2NA UK 1 7 2023 1 7 2023 2023 23 12771 11 2022 12 5 2023 © The Author(s) 2023 https://creativecommons.org/licenses/by/4.0/ Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Background Global health will increasingly be determined by cities. Currently over half of the world’s population, over 4 billion people, live in cities. This systematic scoping review has been conducted to understand what cities are doing to improve health and healthcare for their populations. Methods We conducted a systematic search to identify literature on city-wide initiatives to improve health. The study was conducted in accordance with PRISMA and the protocol was registered with PROSPERO (CRD42020166210). Results The search identified 42,137 original citations, yielding 1,614 papers across 227 cities meeting the inclusion criteria. The results show that the majority of initiatives were targeted at non-communicable diseases. City health departments are making an increasing contribution; however the role of mayors appears to be limited. Conclusion The collective body of evidence identified in this review, built up over the last 130 years, has hitherto been poorly documented and characterised. Cities are a meta-system with population health dictated by multiple interactions and multidirectional feedback loops. Improving health in cities requires multiple actions, by multiple actors, at every level. The authors use the term ‘The Vital 5’. They are the five most important health risk factors; tobacco use; harmful alcohol use; physical-inactivity, unhealthy diet and planetary health. These ‘Vital 5’ are most concentrated in deprived areas and show the greatest increase in low and middle income countries. Every city should develop a comprehensive strategy and action plan to address these ‘Vital 5’. Supplementary Information The online version contains supplementary material available at 10.1186/s12889-023-15908-0. Keywords City Urban Health Transformation Systematic issue-copyright-statement© BioMed Central Ltd., part of Springer Nature 2023 ==== Body pmcBackground Global heath will increasingly be determined by cities. Currently over half (55 per cent) of the world’s population lives in cities and by 2050, 68 percent of the world’s population is projected to be urban [1]. This growth has occurred and will continue to occur over a relatively short period. The world’s cities are growing in both size and number in all regions [2] but there is particularly rapid growth in the number and size of cities across Asia, Africa and South America [3]. For example, between 1950 and 2005, the percentage of the population of China living in cities rose from 13 to 40% and it is predicted to rise to 60.3 percent by 2030 [2]. To put the scale of the urbanisation challenge and opportunity in context, since 2003, China poured more cement every two years than the US did in the entire 20th century [4]. Concrete manufacture accounts for at least 8% of global carbon emissions [5]. This will have a significant impact on environmental health which has both direct and indirect impact on population health. Whilst cities contain some of the best health and healthcare, they also contain a disproportionate share of the worst [6]. There also remains significant variation in health and high levels of inequality [7]. Many urban health and environmental challenges are a consequence of how we organise and live in cities [8] which have resulted in cities that are making people sicker, fatter and more socially isolated [9–11]. Globally cities have been hardest hit by Covid-19 [12]. However, there are also reasons for optimism. Cities are the world's engines of economic growth, innovation, and social change [13]. City living is better for the environment [3] and city dwellers have had better health than their rural counterparts since at least the early to mid-20th century, in high income as well as low and middle income countries [6, 14] Climate change is the number one threat to population health [15–18] and it is cities that are leading the way in becoming carbon neutral [19]. Cities have been shown to succeed—where national governments have failed—in making significant improvements in areas affecting population health [20–26]. It is widely accepted we need to improve equitable health and care in cities. There is good financial imperative to do so; good health is not only a consequence of, but also a condition for sustained and sustainable economic development [27]. In this way, the health of a city creates a virtuous circle of improved health and improved economic prosperity. Not just for the city but for its nation [14]. There is a compelling case to improve health in city populations. The aim of this global systematic scoping review is to provide an overview of the existing evidence of city initiatives to improve health. In addition, a summary of each of the 1614 papers which describe an initiative to improve health or healthcare is provided (Additional file 1) in a format that can be thematically searched. This will be a useful resource for academics and policy makers interested in improving urban health. The outputs of this systematic scoping review should be used to inform urban health policy for the next decade. Methods Aim and overview A systematic search was conducted to identify literature on city-wide initiatives to improve health. This study was completed in accordance with the PRISMA extension for scoping reviews [28] The protocol was registered at PROSPERO (number CRD42020166210). Search strategy and selection criteria Ten databases were searched; Embase, Ovid Medline, Cochrane Database (CENTRAL), Scopus, Campbell Library, CINALH, Health Business Elite, Health Management Information Consortium (HMIC), PyschINFO and Prospero. Specific and pre-determined search terms were developed, tested and finalised for each database. These are available in Additional file 1. The inclusion criteria was: city-wide initiatives that aimed to improve health or healthcare. The definition of improvement, for the purposes of this research, was purposefully broad and included any initiative whose aim was to improve health outcomes or healthcare services. Citations that did not describe an improvement initiative or did describe an improvement initiative but only of a single organisation and not city-wide were excluded. City-wide improvement initiative of family planning services and malaria and dengue fever were excluded. Citations not in English language were also excluded. All databases were searched on the 10 – 12 February 2016, for entries from database inception to February 2016 (tranche 1). The search was updated on 16 March 2019, for entries from February 2016 to March 2019 (tranche 2). Extensive hand searching was also completed. The database results were uploaded to Endnote (version 9) (Fig. 1).Fig. 1 – PRISMA [29] study attrition flow chart Publication selection All types of study design were eligible for inclusion, including grey literature. Studies were not selected or screened based on methodological quality. The key factor was that the study needed to describe a city-wide initiative to improve health or healthcare. All initiatives were included irrespective of how ambitious they were. The primary outcome indicators that were sought and extracted were: improved health or reduced health inequalities; improved healthcare (safety, effectiveness, patient experience); failed initiative or negative or unintended consequences. The first tranche (31,251 original citations) were assessed independently by the lead author (SD) and HLP1 against the inclusion criteria. The level of inter-reviewer agreement on the articles was on average 96% (range 91%—98%). Where there was a disagreement, the two reviewers discussed and agreed on a final outcome. The second tranche was assessed by SD. Where it was uncertain whether the initiatives were city-wide, they were included. Data analysis Predetermined data fields were agreed prior to data extraction. The data fields were; date of publication; type of publication; initiative; how the initiative was implemented; city; city population; country; continent; quantitative outcome; author’s qualitative conclusion. A template (excel) was developed for data extraction and analysis. Where any of this data was not presented, it was coded as ‘not stated’. The only exception to this was with city population. Where this was not presented, the information was sought through world statistics organisation [30]. The latest available population data was used (irrespective of when the initiative took place). The lead author (SD) extracted the data and systematically coded and analysed the data. Studies that did not name a specific city were still included as long as that they indicated they were from a city. Inductive thematic analysis, in line with the guidelines of Braun and Clarke, [31] was carried out as it offered optimum flexibility and breadth. The included studies were not critically appraised for quality. However, the authors have highlighted throughout the text, major methodological issues, source of study heterogeneity and necessary contextual information for interpreting the results. This data was used by the authors to debate and agree the key findings and recommended policy actions. Patient and public involvement This research was done without patient or public involvement. Results The database searches yielded a total of 42,028 original citations after duplicates were removed through Endnote standard duplicate check. These electronic searches were augmented with an additional 109 citations found through expert recommendations or internet searches, giving a total of 42,137 original citations. These citations were assessed and resulted in 1614 citations meeting the inclusion criteria. The full text of the 1614 citations was screened and all included in the inductive thematic coding. The overwhelming majority (90%, n = 1455) of papers were journal articles. The publication date ranged from 1892 to 2019. Subject areas of health improvement A total of 47 themes emerged as subject areas that cities were seeking to address. Just over two thirds (69% n = 1113) of the subject areas were related to improving health, with the remaining 31% (n = 501) related to improving health services. Across improving health and improving healthcare, 92% (n = 1483) were addressing non-communicable diseases (Fig. 2).Fig. 2 Subject area cities were seeking to address Of those related to improving health, 1043 (94%) were focused on non-communicable diseases and 70 (6%) were focused on communicable diseases. In relation to non-communicable diseases, there were 39 different subject areas addressed. A significant proportion (n = 354 equivalent to 33%) did not state a specific area of health they were seeking to address. Where a specific area was stated, the highest was obesity (n = 104), followed by diet (n = 102), smoking (n = 61) and then air quality (n = 53). The non-communicable health subject areas are presented in Fig. 3 below. The communicable diseases [32] included; HIV (n = 44), TB (n = 12), Sexual Transmitted Disease (n = 1), Influenza, Small Pox, Typhoid and others (n = 10).Fig. 3 Non-communicable health subject areas that cities were seeking to address This graph shows subject areas included in five or more citations. Those coded as general health or not stated have been removed. Those relating to improving health services (n = 501) were split across forty thematic areas as shown in Fig. 4 below.Fig. 4 Subject areas that were being addressed through improving healthcare Type of initiative There were 6 categories of initiative identified (Table 1). Education was the most frequently applied type of initiative with 26%, followed closely by service reform (23%) and change to physical environment (21%). A significant proportion (17%) either did not state the type of initiative or it was unclear. Less than a tenth (8%) described a comprehensive initiative and the smallest volume of initiatives were related to digital, data or IT (6%) (Fig. 5).Table 1 Type of initiative Category Definition of category # of papers % Education / support program A programme to education or support the individual(s), either patient / population or workforce. For example, the education initiative to improve healthy lifestyles with a focus on school children [33] 414 26% Service reform A change or addition to a health service, ie improved patient flow redesign or additional outpatient clinic. For example, the description of Shanghai’s service reforms [34] 366 23% Change to physical environment A change to the physical environment to change the world in which the individual interacts. For example, Los Angeles banning fast-food restaurants [35] 336 21% Comprehensive The initiative was described as, and believed to be, a comprehensive initiative (ie more than one single initiative) and / or it contained more than one of these 6 categories. For example, the urban health strategy in Detroit [36] 124 8% Digital / IT / Data A digital or data initiative, or the use of IT more generally, to improve health or healthcare 92 6% Not stated / unclear There was not an initiative or if there was it was not stated in the title or abstract. For example, Taipei’s multi-channel digital risk communications to prevent the spread of a communicable disease [37] 282 17% Fig. 5 Type of initiative per year How the initiative was instigated There were 12 categories which indicated how the initiative was instigated (Table 2). Eight were predetermined ahead of data extraction, four (national or philanthropic funded, research, WHO, Stanford 5 city project) were identified during extraction. Over a third (34%) did not state how the initiative was instigated. Policy (12%), collaboration (12%), service reform (11%) and law (11%) were the next highest methods of instigating an initiative. It is worth noting the contribution of City Health Departments (6%), WHO Healthy Cities (5%) and national or philanthropic (5%). Only 44 (3%) referenced a Mayor as having a significant role (Figure 6) (Table 2). Table 2 Number of papers in each category Categories of ‘how’ initiative was instigated # of papers % Policy 178 11% Collaboration 181 11% Service Reform 247 15% Law 91 6% City Health (or other) Department 163 10% WHO Healthy Cities 51 3% National or Philanthropic 68 4% Fiscal / Financial levers 38 2% Research 55 3% WHO (but not Healthy Cities) 6 0% Stanford 5 City Project 7 0% Not stated 529 33% Fig. 6 How initiatives were instigated each year Location The city in which an initiative was carried out was recorded and coded, as was the country and continent of the city. In addition, the population of the city was recorded if it was stated and if it was not recorded it was sought. The 1614 citations represent initiatives from 227 cities. The majority of cities were just in one paper (n = 179 cites). New York City accounted for nearly one fifth (17% 279 of 1614) of the total papers, followed by Baltimore (51) and London (48). Collectively, these 3 cities (less than 1% of total number of cities) account for nearly a quarter (23%) of all the citations. The 227 cities come from 80 countries across five continents. The USA accounts for the highest number of citations (n = 690), significantly more than the next highest (England with 135 citations). North America accounts for 57% of all the citations (Fig. 7).Fig. 7 Citations per continent The populations of cities ranged from 1,465 (Stevenson, WA, USA) [38] to 23,019,196 (Shanghai, China) [34]. This highlights the vast variation in population size of cities and indicates the breadth of the interpretation and definition of a city. Outcome of the initiatives Outcome was extracted and coded into; 1) no outcome stated; 2) input or process measure; 3) positive outcome measure; or 4) negative outcome. Definition for 2) input or process measure is, for example, Feyerherm et al. [39] which reported on the number of organisations that participated and carried through some subsequent action (input measure). Or, for example, Sacks and Nonas [40] who reported on the outcome of number of adults reported as eating fruit and vegetables (process measure). Definition for 3) positive outcome measure is defined as a measure of health or a measure with a direct health benefit (eg reduced smoking, reduced obesity). For example; Duncan [41] who reported a 40% reduction in emergency department visits by high users (outcome related to healthcare). Or, Coady et al. [42] who reported a 27% decrease in smokers (direct health benefit). Or Weinstein [43] that reported on reduced infant mortality. Finally, an example of a negative outcome would be De Salazar [44] who reported the initiative to reduce prevalence of cardiovascular disease in Cali (Columbia) actually increased sedentary lifestyles. More than half (57%) did not have an outcome recorded. Thirty four percent referenced an input or process measure. Eight percent reported an outcome measure and one percent reported a negative impact as a result of the initiative. It is not possible to describe all the initiatives in detail in this manuscript. Therefore, an excel file is provided with all records and data extraction and analysis is available in Additional file 2. This Additional file can be used as a resource for policy makers and researchers to further interrogate and build on the data. Discussion There is growing interest in the actions that cities are taking to improve health and healthcare. This is in keeping with the increasing importance of cities in determining global population health. The earliest initiative was the House of Lords Select Committee Report on Metropolitan Hospitals, Provident and Other Public Dispensaries and Charitable Institutions for the Sick Poor, [45] published in 1892. Whilst the social context and healthcare delivery have developed significantly, the issues identified in this report, including the need for co-ordination between services and unacceptable inequalities, remain as relevant today. The collective body of evidence identified in this review, built up over the last 130 years, has hitherto been poorly documented and characterised. This may in part explain why longstanding issues remain pertinent today. Education was the most frequently applied type of initiative (26%), with the trend increasing over time. It consistently features as one of the most reported initiatives in the last 15 years. With non-communicable diseases – often referred to as ‘life style choices’ [46, 47]—being such a high proportion (92%) of the subject areas that initiatives were seeking to address, it is perhaps not surprising that education features so strongly. Education initiatives tend to be straightforward to write up and evaluate [48], which lends them towards publication. They are also commonly associated with funding [49] that requires some kind of evaluation or report, which again lends towards publication. However, in our experience, trying to change individual behaviour without changing the system or environment within which people live does not work. The term ‘life style choices’is a misnomer. The reality is that we are strongly influenced by explicit and implicit prompts in our environment and those with the least resources have the least choice and are the most lectured. Changes to the physical environment is linked with changing the environment within which we live. It was therefore disappointing that these types of initiatives accounted for only 21% (n = 336) of the total. It was also disappointing that only 21 of the 336 reported an outcome measure. These were addressing issues of obesity [50, 51] smoking [52–54] water borne infections [55–57], traffic related accidents and active travel [58–62]. These changes to physical environment were instigated by policy or legal changes in just under half (43%) of the initiatives. In considering the balance between education and system or environmental initiatives, more focus and effort should be on system and environment to ‘make the healthy choice the easy choice’. Service reform (23% of the total citations) performed best on reporting an outcome measure (n = 34). These ranged from centralising heart attack and stroke services, [63, 64] injection drug user facilities for harm reduction, [65] decentralising and creating networks for care for diabetes [66] and dementia [67] to mass nicotine replacement therapy [32]. Service reform, which is defined as ‘a change or addition to a health service’, is akin to a change to the physical environment or system within which we live. It is also most directly linked to health services. Therefore, service reforms have a direct and clear link to any changes in outcomes. This is not to say the changes are easy or straightforward. Changing any provision of health service, particularly if controversial services or moving services further from a patient’s home, is likely to understandably attract public and political interest. Clinical leadership and genuine public and political engagement are key. A relatively small number (n = 124) of initiatives described what was believed to be a comprehensive suite of initiatives. City health departments were most notable in leading these in a diverse range of cities including New York City (USA), [68] Geelong (Australia), [69] Barcelona (Spain), [70] Taipei (Tiawan) [71] to Nizwa (Oman) [72]. Coincidently, there were also 124 records that stated an outcome measure. It is striking that although a comprehensive approach only represented 8% of the total, they represent almost a quarter (23%) of the number with an outcome measure. There could be a number of reasons why outcome measures feature strongly when a comprehensive suite of initiatives is undertaken. A range of initiatives addressing the same subject area may be more likely to bring about a change in outcome compared to a single initiative. City Health Departments are strongly associated with City Mayors. However, of the 1614 citations only 44 (3%) referenced a Mayor as having any kind of role. Considering Mayors are such features of cities, this was surprising. It was also notable, in general, that initiatives across all areas appeared quite piecemeal and carried out in insolation; a single initiative linked to a single health issue or risk factor without reference to a wider strategy, aim or other supporting initiatives. This could simply be a product of the way the papers were written. Indeed, there is a neat simplicity to this approach. However, the reality of the real world is that a single initiative is unlikely to making meaningful and lasting impact on long-standing issues. Cities are a meta-system with population health dictated by multiple interactions and multidirectional feedback loops. A change to one part of the system could both result in multiple unintended consequences or no impact on outcomes at all. Improving health in cities requires multiple actions, by multiple actors, at multiple levels. No single organisation, sector or initiative can solve the complex interlinked issues. The political and system leadership across a collaboration of partners by a Mayor will be crucial. The role and impact of Mayors in city residents’ health would warrant further investigation. The initiative itself also affected how it was instigated (Table 3). It should be noted that “not stated” featured highly across all groups, ranging up to 54% in education and support and totalling 529 (33%) across all initiatives. Therefore, care should be taken with interpreting this result. The comprehensive initiatives were broadly split one fifth policy, collaboration and city health department, with 20%, 18%, 27%, respectively. Education initiatives were most associated with collaboration (15%), city health department (9%) and policy (6%). Changes made to the physical environment were strongly associated with policy (22%) and law (21%).Digital, IT and data was most commonly instigated by city health departments (21%) (Table 3).Table 3 Type of initiative and how it was instigated Type of Initiative # of papers % How Intervention Instigated How Instigated volume How Instigated percentage # with outcome measure Percentage of the total of those with an outcome Comprehensive 124 8% Policy 25 20.2% 3 2.4% Collaboration 22 17.7% 1 0.8% Service Reform 0 0.0% 0 0.0% Law (4) 1 0.8% 1 0.8% City Health Dept 34 27.4% 17 13.7% Fiscal (6) 0 0.0% 0 0.0% Research 1 0.8% 0 0.0% National or philanthropc 7 5.6% 0 0.0% WHO Healthy Cities (9) 6 4.8% 0 0.0% WHO 1 0.8% 0 0.0% Stanford (11) 0 0.0% 0 0.0% Not stated 27 21.8% 7 5.6% Education / support program 414 26% Policy 26 6.3% 2 1.6% Collaboration 63 15.2% 4 3.2% Service Reform 9 2.2% 0 0.0% Law (4) 8 1.9% 0 0.0% City Health Dept 36 8.7% 2 1.6% Fiscal (6) 3 0.7% 4 3.2% Research 16 3.9% 0 0.0% National or philanthropc 19 4.6% 1 0.8% WHO Healthy Cities (9) 3 0.7% 0 0.0% WHO 2 0.5% 0 0.0% Stanford (11) 7 1.7% 3 2.4% Not stated 222 53.6% 14 11.3% Change to physical environment 336 21% Policy 75 22.3% 1 0.8% Collaboration 17 5.1% 1 0.8% Service Reform 4 1.2% 1 0.8% Law (4) 69 20.5% 4 3.2% City Health Dept 27 8.0% 0 0.0% Fiscal (6) 16 4.8% 1 0.8% Research 8 2.4% 0 0.0% National or philanthropc 10 3.0% 2 1.6% WHO Healthy Cities (9) 4 1.2% 0 0.0% WHO 1 0.3% 0 0.0% Stanford (11) 0 0.0% 0 0.0% Not stated 105 31.3% 11 8.9% Service reform 366 23% Policy 14 3.8% 0 0.0% Collaboration 47 12.8% 4 3.2% Service Reform 228 62.3% 25 20.2% Law (4) 7 1.9% 1 0.8% City Health Dept 31 8.5% 3 2.4% Fiscal (6) 18 4.9% 0 0.0% Research 2 0.5% 0 0.0% National or philanthropc 19 5.2% 1 0.8% WHO Healthy Cities (9) 0 0.0% 0 0.0% WHO 0 0.0% 0 0.0% Stanford (11) 0 0.0% 0 0.0% Not stated 0 0.0% 0 0.0% Digital / IT / Data 92 6% Policy 2 2.2% 0 0.0% Collaboration 5 5.4% 1 0.8% Service Reform 6 6.5% 0 0.0% Law (4) 0 0.0% 0 0.0% City Health Dept 19 20.7% 1 0.8% Fiscal (6) 1 1.1% 0 0.0% Research 7 7.6% 0 0.0% National or philanthropc 4 4.3% 0 0.0% WHO Healthy Cities (9) 3 3.3% 0 0.0% WHO 0 0.0% 0 0.0% Stanford (11) 0 0.0% 0 0.0% Not stated 45 48.9% 2 1.6% Not stated / no intervention 282 17% Policy 36 12.8% 2 1.6% Collaboration 27 9.6% 0 0.0% Service Reform 0 0.0% 2 1.6% Law (4) 6 2.1% 0.0% City Health Dept 16 5.7% 0 0.0% Fiscal (6) 0 0.0% 0 0.0% Research 21 7.4% 0 0.0% National or philanthropc 9 3.2% 0 0.0% WHO Healthy Cities (9) 35 12.4% 0 0.0% WHO 2 0.7% 0 0.0% Stanford (11) 0 0.0% 0 0.0% Not stated 130 46.1% 2 1.6% Total citations with an outcome measure: 124 The majority of papers were from North America (57% of total, almost double the total of Europe) and in particular New York City which alone accounted for 17% (n = 279) of the total, more than the entire WHO Healthy City output found. It is not clear if this is because New York City is taking significant steps to improve health and healthcare or they are publishing a lot of their work, or both. This features in the bias and limitations identified in the section below. It also highlights the opportunity for further study through a survey of city health departments to get a more complete picture of the initiatives that cities are undertaking to improve population health. The breadth of subject areas being addressed from a number of different perspectives and the interrelated nature of the subject areas is striking. For example, diet is known to impact on obesity, [73] and cancer [74], and cardiovascular [75] disease. Obesity is known to impact on cancer, [76] cardiovascular, [77] mental health [78] and mental health is known to impact on obesity [79]. Therefore, an initiative to improve diet could be an initiative to address obesity, cancer, cardiovascular disease, mental health or health generally. The complexity of a range of subject areas being addressed could be simplified when the major causes of chronic diseases are well known. Indeed, the four main risk factors (tobacco use; harmful alcohol use; physical inactivity and unhealthy diet) account for at least 80% of all heart disease, stroke and type 2 diabetes and 40% of cancers [80]. The authors would add a fifth risk factor; planetary health. Planetary health is widely acknowledged to be a significant risk to human health [81–83] particularly impacting cities [84, 85]. The health risk factors are also directly linked to planetary health factors, for example diet [86] and evidence shows polices to promote sustainable food supply can improve personal and planetary health [87]. The authors would call these ‘The Vital 5’. They are the 5 most important health risk factors. These ‘Vital 5’ are most concentrated in deprived areas [88] and show the greatest increase is in low and middle income countries, even faster than has historically occurred in high income countries [89]. Therefore, action on these ‘Vital 5’ will be action on inequalities. Every city should develop a comprehensive strategy and action plan to address these ‘Vital 5’ of tobacco use; harmful alcohol use; physical inactivity, unhealthy diet and planetary health. The 20th century was defined by breakthroughs in communicable diseases. Communicable diseases are certainly not eradicated; HIV [90–92] and TB [93–95] can still be seen to be particular issues in cities. The Covid-19 pandemic has also disproportionately impacted cities [12]. However, Covid-19 has also reminded us of the importance of these Vital 5. It is known that smoking, [96] alcohol, [97] poor diet, [98] physical inactivity [99] and air quality [100], all contribute to worse outcomes of Covid-19. They also contribute to other factors which have worse outcomes of Covid-19, such as high blood pressure [101] and obesity [102]. Crucially, it is also know that damaging the environment will make future pandemics more likely [103, 104]. If cities were to focus on these Vital 5 they would be improving immediate and long term population health. This study has several limitations. The deliberate decision was taken to be as broad and inclusive as possible in the papers included. Mays et al. [105] and Strech and Tilburt [106] identify the tension between using only academically rigorous, but therefore less, research and the inclusion of other sources of data, which increase the volume, but that are more susceptible to bias and therefore risk contaminating results. Because of the volume of papers and restrictions on time only, the title and abstract were used in the data extraction. Formal quality assessment of the studies was not undertaken. Only studies in English language were included. A large volume of citations were from one city (New York City) which could introduce bias. Finally, given the heterogeneity of the study designs and data sources, meta-analysis was not undertaken. The authors acknowledge that despite a comprehensive and systematic approach they may have missed relevant documentation. The authors believe non-communicable diseases will be the issue of the 21st century, accounting for over 40 million annual deaths globally (72% of total deaths) [107]. The Vital 5; tobacco use; harmful alcohol use; physical inactivity, unhealthy diet and planetary health impact on both non-communicable diseases and the likelihood of future communicable pandemics. The progress made in the treatment and prevention of HIV from death sentence 20 years ago to entirely treatable and preventable long-term condition, plus the rapid response to Covid-19 demonstrates what could be achieved to eliminate these ‘Vital 5’ with collective determination and resources. Cities have demonstrated they are well placed to take this action. Conclusions This global systematic scoping review provides an overview of the existing evidence of city initiatives to improve health and healthcare. Based on the findings, a summary of key findings and recommended policy actions is provided below. This, with the excel file with the 1614 records and associated extracted data (Additional file 2), will be a useful resource for academics and policy makers interested in improving urban health. The outputs of this systematic scoping review can be used to inform urban health policy for the next decade and shape future research. The role of Mayors and the real world understanding of the initiatives that city health departments are undertaking to improve population health warrants particular attention. Key findings and recommended policy actions:Key Finding: There is a large range of health issues and risk factors being addressed from a large number of perspectives. The overwhelming majority of the issues and initiative are addressing ‘non-communicable disease’ risk factors that are interrelated and overlapping. Recommended Policy Action: The same level of ambition that was applied to HIV and Covid-19 should be applied to the ‘Vital 5’ risk factors; smoking, alcohol, physical inactivity, unhealthy diet and planetary health. Key Finding: Education was the most commonly reported initiative. Recommended Policy Action: The term ‘lifestyle choices’ is a misnomer. More focus and resource should be put on system and environmental changes to ‘make the healthy choice the easiest choice’ Key Finding: City health departments are making an increasing contribution in improving city population health. Recommended Policy Action: Cities should collaborate and share learning in real world experience of initiatives to improve urban health. Key Finding: The contribution of Mayors in improving health and healthcare appears to be limited Recommended Policy Action: The role and impact of Mayors in city populations would warrant further study Key Finding: New York City stands out with nearly one fifth (18%) of the total citations. Recommended Policy Action: Further real world research to understand and get a comprehensive view on what cities are doing to improve population health would be of value. Supplementary Information Additional file 1. Database Search Strings. Additional file 2. Abbreviations Covid-19 Coronavirus disease 2019 PRISMA Preferred Reporting Items for Systematic Reviews and Meta-Analyses PROSPERO International prospective register of systematic reviews HLP Healthy London Partnership. HIV Human immunodeficiency virus TB Tuberculosis WHO World Health Organisation IT Information Technology Acknowledgements We would like to thank the members of the Healthy London Partnership (HLP)* that helped on providing a second review of titles and abstracts. These were: Patrice Donnelly, Pascale Montiel, Emily Treder, Natalia Proctor, Sarah Bowker, Claire Ruiz, Lauren Walker, Dominic Jones, Suzi Griffiths, Steve Solasta, Jess Simpson, Raman Patria, David Groom, Emile Radyte, Amy Bowkett, Helen Daly, Jess Drummond, Gabriella Baker, Martina Dalton, Andrea Priest, Tanmay Kale, Lise Hansen and Katie Horrell. Authors’ contributions Conception or design of the research: SD. Data collection: SD. Data analysis and interpretation: SD, HA, AD. Drafting the article: SD, HA. Critical revision of the article: SD, HA, AD. All authors read and approved final manuscript. Authors’ information SD is Director of Population Health and Equality at Kings Health Partners and South East London Integrated Care System. He has led transformation of health and healthcare across London for over 13 years. HA is Chief Scientific Advisor at the Institute of Global Health Innovation (Imperial College London) and has led and supervised multiple research projects. AD is the Co-director at the Institute of Global Health Innovation Imperial College London. He has led many city and national reviews of health and health care. Funding This manuscript received no specific funding. Infrastructure support for this research was provided by the NIHR Imperial Biomedical Research Centre (BRC). Availability of data and materials The data generated from this review is provided in the supplementary information files. Declarations Ethics approval and consent to participate Not applicable. Consent for publication Not applicable. Competing interests AD is Chair and HA the Chief Scientific Officer of the Health Security Initiative at Flagship Pioneering UK Ltd. SD has no competing interests to declare. 1 See acknowledgements for full list. Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. ==== Refs References 1. United Nations. 2018 Revision of World Urbanization Prospects 2018 [Available from: https://www.un.org/development/desa/publications/2018-revision-of-world-urbanization-prospects.html. 2. United Nations. Department of Economic and Social Affairs, Population Division (2018). The World’s Cities in 2018—Data Booklet (ST/ESA/ SER.A/417). 2018. p. 2. https://www.un.org/en/development/desa/population/publications/pdf/urbanization/the_worlds_cities_in_2018_data_booklet.pdf. 3. Satterthwaite D Will most people live in cities? BMJ (Clinical Res Ed) 2000 321 7269 1143 1145 10.1136/bmj.321.7269.1143 4. Hawkins A The grey wall of China: inside the world's concrete superpower The Guardian 2019 2019 28 5. Ellis LD Badel AF Chiang ML Park RJY Chiang YM Toward electrochemical synthesis of cement—An electrolyzer-based process for decarbonating CaCO3 while producing useful gas streams Proc Natl Acad Sci 2020 117 23 12584 91 10.1073/pnas.1821673116 31527245 6. Ezzati M Webster CJ Doyle YG Rashid S Owusu G Leung GM Cities for global health BMJ 2018 363 k3794 10.1136/bmj.k3794 30282765 7. Vlahov D Fraudenberg N Proietti F Ompad D Quinn A Nandi V Galea S Urban as a determinant of health J Urban Health. 2007 84 SUPPL.1 i16 i26 10.1007/s11524-007-9169-3 17356903 8. Dodman D Blaming cities for climate change? An analysis of urban greenhouse gas emissions inventories Environ Urban 2009 21 1 185 201 10.1177/0956247809103016 9. Montgomery C Happy City: Transforming Our Lives Through Urban Design 2013 Kindle New York Penguin 10. Sureda X Villalbí JR Espelt A Franco M Living under the influence: normalisation of alcohol consumption in our cities Gac Sanit 2017 31 1 66 68 10.1016/j.gaceta.2016.07.018 27769724 11. Kuddus MA Tynan E McBryde E Urbanization: a problem for the rich and the poor? Public Health Rev 2020 41 1 1 10.1186/s40985-019-0116-0 31908901 12. United Nations. Policy Brief: COVID-19 in an Urban World 2020 [Available from: https://www.un.org/sites/un2.un.org/files/sg_policy_brief_covid_urban_world_july_2020.pdf. 13. Colenbrander S. Cities as engines of economic growth The case for providing basic infrastructure and services in urban areas 2016 [Available from: https://pubs.iied.org/sites/default/files/pdfs/migrate/10801IIED.pdf. 14. Dye C Health and urban living Science 2008 319 5864 766 769 10.1126/science.1150198 18258905 15. Lancet T A commission on climate change The Lancet 2009 373 9676 1659 10.1016/S0140-6736(09)60922-3 16. Wight J Middleton J Climate change: the greatest public health threat of the century BMJ 2019 365 l2371 10.1136/bmj.l2371 31160333 17. Watts N Adger WN Agnolucci P Blackstock J Byass P Cai W Health and climate change: policy responses to protect public health The Lancet 2015 386 10006 1861 1914 10.1016/S0140-6736(15)60854-6 18. Watts N Amann M Arnell N Ayeb-Karlsson S Belesova K Boykoff M The 2019 report of the lancet countdown on health and climate change: ensuring that the health of a child born today is not defined by a changing climate The Lancet. 1836 2019 394 19. Robertson D. Inside Copenhagen’s race to be the first carbon-neutral city. The Guardian. 2019. https://www.theguardian.com/cities/2019/oct/11/inside-copenhagens-race-to-be-the-first-carbon-neutral-city. Accessed 17 June 2021. 20. Naylor C, Buck D. The role of cities in improving population health: international insights: Kings Fund; 2018 [Available from: https://www.kingsfund.org.uk/sites/default/files/2018-06/Role_cities_population_health_Kings_Fund_June_2018_0.pdf. 21. Davies SC. Annual report of the chief medical officer 2019 [Available from: https://www.gov.uk/government/publications/chief-medical-officer-annual-report-2019-partnering-for-progress. 22. Danielli S Coffey T Ashrafian H Darzi A Systematic review into city interventions to address obesity EClinicalMedicine 2021 32 100710 10.1016/j.eclinm.2020.100710 33681735 23. Diller P. Why do Cities innovate in public health? Implications of scale and structure 2014 [Available from: https://openscholarship.wustl.edu/cgi/viewcontent.cgi?referer=&httpsredir=1&article=6092&context=law_lawreview. 24. Barber B. If Mayors Ruled the World. Connecticut: Yale University Press; Reprint edition (September 30, 2014); 2014. 25. Hoornweg D Pope K Population predictions for the world’s largest cities in the 21st century Environ Urban 2016 29 1 195 216 10.1177/0956247816663557 26. Theis D White M Is obesity policy in England fit for purpose? Analysis of government strategies and policies, 1992–2020 Milbank Q 2021 99 1 126 170 10.1111/1468-0009.12498 33464689 27. Frenk J Health and the economy Harvard Int Rev 2014 35 4 62 64 28. Tricco AC Lillie E Zarin W O'Brien KK Colquhoun H Levac D PRISMA extension for scoping reviews (PRISMA-ScR): checklist and explanation Ann Intern Med 2018 169 7 467 473 10.7326/M18-0850 30178033 29. Moher D Liberati A Tetzlaff J Altman DG Group P Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement PLoS Med 2009 6 7 e1000097-e 10.1371/journal.pmed.1000097 19621072 30. World Statistics Organisation. Population of Localities 2018 [Available from: https://world-statistics.org/index-pop.php. 31. Braun V Clarke V Using thematic analysis in psychology Qual Res Psychol 2006 3 2 77 101 10.1191/1478088706qp063oa 32. Miller N Frieden ThomasR Liu SzeYan Matte ThomasD Mastashari Farzad Deitcher DeborahR Cummings K Chang Christina Bauer Ursula Bassett MaryT Effectiveness of a large-scale distribution programme of free nicotine patches: A prospective evaluation The Lancet. 2005 365 9474 1849 54 10.1016/S0140-6736(05)66615-9 33. Peñalvo JL Sotos-Prieto M Santos-Beneit G Pocock S Redondo J Fuster V The program SI! intervention for enhancing a healthy lifestyle in preschoolers: first results from a cluster randomized trial BMC Public Health 2013 13 1 1 10.1186/1471-2458-13-1208 23280303 34. Tsung-Mei C Explaining Shanghai’s health care reforms, successes and challenges Health Affairs 2013 32 12 2199 205 10.1377/hlthaff.2013.1136 24197128 35. Sturm R Cohen DA Zoning For Health? The Year-Old Ban On New Fast-Food Restaurants In South LA Health Affairs. 2009 28 w1088-NaN 10.1377/hlthaff.28.6.w1088 19808703 36. Whitelaw N Warden G Wenzler MR Current efforts toward implementation of an urban health strategy: The Henry Ford Health System J Urban Health 1998 75 2 356 66 10.1007/BF02345103 9684247 37. Yen MY Wu TSJ Chiu AWH Wong WW Wang PE Chan TC King CC Taipei's use of a multi-channel mass risk communication program to rapidly reverse an epidemic of highly communicable disease PLoS ONE 2009 4 11 e7962 10.1371/journal.pone.0007962 19956722 38. Tran AD Addressing eating habits through food label education in Stevenson, WA J Investig Med 2010 58 1 204 39. Feyerherm L, Tibbits M, Wang H, Schram S, Balluff M. Partners for a healthy city: implementing policies and environmental changes within organizations to promote health. Am J Public Health. 2014;104(7):1165–8. 40. Sacks RY, S. S.; Nonas, C. Increasing access to fruits and vegetables: perspectives from the New York City experience. American journal of public health. 2015;105(5):e29-e37. 41. Duncan BR New healthcare model: Citywide care management Otolaryngol - Head Neck Surg (United States) 2012 147 P125 42. Coady MH, Chan CA, Auer K, Farley SM, Kilgore EA, Kansagra SM. Awareness and impact of New York City's graphic point-of-sale tobacco health warning signs. Tobacco Control. 2012. 43. Weinstein I Eighty years of public health in New York City Bull N Y Acad Med 1947 23 4 221 237 19312527 44. de Salazar L Linking public health surveillance systems to program effectiveness evaluation Colombia Medica 2011 42 3 342 351 10.25100/cm.v42i3.881 45. House of Lords. Third report of the select committee of the house of lords on metropolitan hospitals. The Lancet. 1892;140(3592):49–52. https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(01)97445-8/fulltext. (Kings Fund library on 16 November 2022). 46. Kickbusch I Allen L Franz C The commercial determinants of health Lancet Glob Health 2016 4 12 e895 e896 10.1016/S2214-109X(16)30217-0 27855860 47. Wainwright NWJ Surtees PG Welch AA Luben RN Khaw K-T Bingham SA Healthy lifestyle choices: could sense of coherence aid health promotion? J Epidemiol Community Health 2007 61 10 871 876 10.1136/jech.2006.056275 17873222 48. Nana-Goar Pogosova NE, A.; Ausheva, A. Evaluation of the efficacy of cardiovascular prevention in the framework of the World Heart Day. European Journal of Preventive Cardiology. 2015 (1);S115. 49. Taing D, McKay K. Better Strength, Better Balance! Partnering to deliver a fall prevention program for older adults. Can J Public Health. 2017;108(3):e314-e319. 10.17269/CJPH.108.5901. 50. Economos CDH, R. R.; Must, A.; Goldberg, J. P.; Kuder, J.; Naumova, E. N.; Collins, J. J.; Nelson, M. E. Shape Up Somerville two-year results: A community-based environmental change intervention sustains weight reduction in children. Preventive medicine. 2013; 57(4):[322–7 pp.]. Available from: http://onlinelibrary.wiley.com/o/cochrane/clcentral/articles/426/CN-00910426/frame.html; http://ac.els-cdn.com/S009174351300193X/1-s2.0-S009174351300193X-main.pdf?_tid=b201df18-cfe8-11e5-9735-00000aab0f6c&acdnat=1455103583_2cfe0f0018bc97c80ed35598a603b6cf. 51. Sekhobo J Edmunds L Dalenius K Jernigan J Davis C Giddings M Neighborhood disparities in prevalence of childhood obesity among low-income children before and after implementation of New York City child care regulations Prev Chronic Dis 2014 11 E181 10.5888/pcd11.140152 25321632 52. Page RL Slejko JF Libby AM A citywide smoking ban reduced maternal smoking and risk for preterm births: a colorado natural experiment J Women’s Health 2012 21 6 621 7 10.1089/jwh.2011.3305 53. Cesaroni G Forastiere F Agabiti N Valente P Zuccaro P Perucci CA Effect of the Italian smoking ban on population rates of acute coronary events Circulation 2008 117 9 1183 8 10.1161/CIRCULATIONAHA.107.729889 18268149 54. Bartecchi C Alsever RN Nevin-Woods C Thomas WM Estacio RO Bartelson BB Krantz MJ Reduction in the incidence of acute myocardial infarction associated with a citywide smoking ordinance Circulation. 2006 114 14 1490 6 10.1161/CIRCULATIONAHA.106.615245 17000911 55. Barreto ML Genser B Strina A Teixeira MG Assis AMO Rego RF Teles CA Prado MS Matos SM Santos DN dos Santos LA Cairncross S Effect of city wide sanitation programme on reduction in rate of childhood diarrhoea in northeast Brazil: assessment by two cohort studies Lancet 2007 370 9599 1622 8 10.1016/S0140-6736(07)61638-9 17993362 56. Cutler D Miller G The role of public health improvements in health advances: the twentieth-century United States Demography. 2005 42 1 1 22 10.1353/dem.2005.0002 15782893 57. Ogasawara K Shirota S Kobayashi G Public health improvements and mortality in interwar Tokyo: a Bayesian disease mapping approach Cliometrica 2018 12 1 1 31 10.1007/s11698-016-0148-3 58. Huitema BE Van Houten R Manal H Time-series intervention analysis of pedestrian countdown timer effects Accident Analys Prev 2014 72 23 31 10.1016/j.aap.2014.05.025 59. Muennig PA Epstein M Li G DiMaggio C The cost-effectiveness of New York City's safe routes to school program Am J Public Health 2014 104 7 1294 9 10.2105/AJPH.2014.301868 24832430 60. Rojas-Rueda D de Nazelle Audrey Tainio Marko Nieuwenhuijsen MarkJ The health risks and benefits of cycling in urban environments compared with car use: health impact assessment study BMJ: Brit Med J 2011 343 7819 1 8 61. Tapia V Carbajal L Vásquez V Espinoza R Vásquez-Velásquez C Steenland K Traffic regulation and environmental pollution by particulate material (2.5 and 10), sulfur dioxide, and nitrogen dioxide in Metropolitan Lima, Peru Rev Peru Med Exp Salud Publica 2018 35 2 190 7 10.17843/rpmesp.2018.352.3250 30183915 62. Nieuwenhuijsen MJ Khreis H Car free cities: pathway to healthy urban living Environ Int 2016 94 251 262 10.1016/j.envint.2016.05.032 27276440 63. Marcolino M Brant LC de Guimaraes C de Araujo JG Nascimento BR Castro LR Martins P Lodi-Junqueira L Ribeiro AL The implementation of the myocardial infarction system of care in a large city in Brazil Global Heart. 2014 9 1 193 10.1016/j.gheart.2014.03.1918 64. Hunter RM Davie C Rudd A Thompson A Walker H Thomson N Mountford J Schwamm L Deanfield J Thompson K Dewan B Mistry M Quoraishi S Morris S Impact on clinical and cost outcomes of a centralized approach to acute stroke care in London: a comparative effectiveness before and after model PLoS ONE. 2013 8 8 e70420 10.1371/journal.pone.0070420 23936427 65. Jozaghi EA Martin A Should North America's first and only supervised injection facility (InSite) be expanded in British Columbia, Canada? Harm Reduct J 2013 10 1 10.1186/1477-7517-10-1 23414093 66. Rea RLJ Gregory S Prescott D Gray T Warren A Hannah J Langeland L Dhindsa P Tan G First diabetes: A successful integrated healthcare partnership for diabetes patients in Derby Diab Med 2012 29 94 67. Tanaka M Medical care networks for dementia patients Jap Med Assoc J 2013 56 4 240 245 68. Ong PLG, Demmer R. Evaluating the influence of bloomberg era policy on New York city cardiovascular disease mortality rates. Circulation Conference: American Heart Association's Epidemiology and Prevention/Lifestyle and Cardiometabolic Health. 2015;131(Suppl_1):(Supplement 1):AMP08. 69. Foulkes C Lessons from healthy together geelong: Delivering systems change at scale across two levels of government Obes Res Clin Pract 2014 8 33 70. Roset-Elias MA Cardena-Franquet E Puigdueta-Lucas I Obea-Maso M What a city council can do to improve the quality of life in the elderly? Ann Nutr Metab 1846 2013 63 71. Yu LH Cancer prevention and therapy in Taipei city Int J Urol 2010 17 A17 A18 72. Alanqoudi Z, Alhinai S. Nizwa healthy lifestyle project evaluation report 2010. 2010. https://www.emro.who.int/health-education/physical-activity-case-studies/the-nizwa-healthy-lifestyles-project-oman.html. Accessed 10 Apr 2021. 73. Cecchini M Sassi F Lauer JA Lee YY Guajardo-Barron V Chisholm D Tackling of unhealthy diets, physical inactivity, and obesity: health effects and cost-effectiveness The Lancet 2010 376 9754 1775 1784 10.1016/S0140-6736(10)61514-0 74. Key TJ Bradbury KE Perez-Cornago A Sinha R Tsilidis KK Tsugane S Diet, nutrition, and cancer risk: what do we know and what is the way forward? BMJ 2020 368 m511 10.1136/bmj.m511 32139373 75. Afshin A Sur PJ Fay KA Cornaby L Ferrara G Salama JS Health effects of dietary risks in 195 countries, 1990–2017: a systematic analysis for the global burden of disease study 2017 The Lancet 2019 393 10184 1958 1972 10.1016/S0140-6736(19)30041-8 76. Lancet T The link between cancer and obesity The Lancet 2017 390 10104 1716 10.1016/S0140-6736(17)32659-4 77. Carbone S Canada JM Billingsley HE Siddiqui MS Elagizi A Lavie CJ Obesity paradox in cardiovascular disease: where do we stand? Vascular Health Risk Management 2019 15 89 100 10.2147/VHRM.S168946 31118651 78. Sarwer DB Polonsky HM The Psychosocial Burden of obesity Endocrinol Metab Clin North Am 2016 45 3 677 688 10.1016/j.ecl.2016.04.016 27519139 79. Kivimäki M Lawlor DA Singh-Manoux A Batty GD Ferrie JE Shipley MJ Common mental disorder and obesity: insight from four repeat measures over 19 years: prospective Whitehall II cohort study BMJ 2009 339 b3765 10.1136/bmj.b3765 19808765 80. World Health Organization Preventing chronic diseases : a vital investment : WHO global report 2005 Geneva World Health Organization 81. Sheffield PE Herrera M Kinnee EJ Clougherty JE Not so little differences: variation in hot weather risk to young children in New York City Public Health 2018 161 119 126 10.1016/j.puhe.2018.06.004 29960726 82. Sewe MO Bunker A Ingole V Egondi T Åström DO Hondula DM Estimated effect of temperature on years of life lost: A retrospective time-series study of low-, middle-, and high-income regions Environ Health Perspect 2018 126 1 017004 10.1289/EHP1745 29342452 83. Frumkin H Haines A Global environmental change and noncommunicable disease risks Annu Rev Public Health 2019 40 1 261 282 10.1146/annurev-publhealth-040218-043706 30633714 84. Rosenthal JK Sclar ED Kinney PL Knowlton K Crauderueff R Brandt-Rauf PW Links between the built environment, climate and population health: interdisciplinary environmental change research in New York City Ann Acad Med Singap 2007 36 10 834 846 10.47102/annals-acadmedsg.V36N10p834 17987235 85. Xiong X Zhang L Hao Y Zhang P Chang Y Liu G Urban dietary changes and linked carbon footprint in China: a case study of Beijing J Environ Manage 2020 255 109877 10.1016/j.jenvman.2019.109877 31778867 86. Swinburn BA Kraak VI Allender S Atkins VJ Baker PI Bogard JR The global syndemic of obesity, undernutrition, and climate change: the lancet commission report Lancet 2019 393 10173 791 846 10.1016/S0140-6736(18)32822-8 30700377 87. Willett W Rockström J Loken B Springmann M Lang T Vermeulen S Food in the anthropocene: the EAT–Lancet commission on healthy diets from sustainable food systems The Lancet 2019 393 10170 447 492 10.1016/S0140-6736(18)31788-4 88. Macdonald L Olsen JR Shortt NK Ellaway A Do ‘environmental bads’ such as alcohol, fast food, tobacco, and gambling outlets cluster and co-locate in more deprived areas in Glasgow City, Scotland? Health Place 2018 51 224 231 10.1016/j.healthplace.2018.04.008 29747132 89. Stuckler D McKee M Ebrahim S Basu S Manufacturing epidemics: the role of global producers in increased consumption of unhealthy commodities including processed foods, alcohol, and tobacco PLoS Med 2012 9 6 e1001235 10.1371/journal.pmed.1001235 22745605 90. Fisher HH Hoyte T Purcell DW van Handel M Williams W Krueger A Dietz P Stratford D Heitgerd J Dunbar E Wan C Linley LA Flores SA Health department HIV prevention programs that support the national HIV/AIDS strategy: The enhanced comprehensive HIV prevention planning project, 2010–2013 Public Health Reports 2016 131 1 185 94 10.1177/003335491613100126 26843685 91. Evans C Suggs LS Turner K Occa A Juma A Blake H Mobile phone messaging to promote uptake of HIV testing among migrant African communities in the UK Health Educ J 2018 78 1 24 37 10.1177/0017896918785928 92. Ard KL Edelstein ZR Bolduc P Daskalakis D Gandhi AD Krakower DS Public health detailing for human immunodeficiency virus pre-exposure prophylaxis Clin Infect Dis 2019 68 5 860 864 10.1093/cid/ciy573 30020422 93. Lam CK McGinnis Pilote K Haque A Burzynski J Chuck C Macaraig M Using video technology to increase treatment completion for patients with latent tuberculosis infection on 3-month isoniazid and rifapentine: an implementation study J Med Internet Res 2018 20 11 e287 10.2196/jmir.9825 30459146 94. Qader G Hamim A Sayedi M Rashidi M Manzoor L Seddiq MK Addressing tuberculosis control in fragile states: Urban DOTS experience in Kabul, Afghanistan, 2009–2015 PLoS ONE 2017 12 5 e0178053 10.1371/journal.pone.0178053 28562675 95. Tabuchi T Takatorige T Hirayama Y Nakata N Harihara S Shimouchi A Tuberculosis infection among homeless persons and caregivers in a high-tuberculosis-prevalence area in Japan: a cross-sectional study BMC Infect Dis 2011 11 1 22 10.1186/1471-2334-11-22 21255421 96. Patanavanich R Glantz SA Smoking is associated with worse outcomes of COVID-19 particularly among younger adults: a systematic review and meta-analysis BMC Public Health 2021 21 1 1554 10.1186/s12889-021-11579-x 34399729 97. Finlay I Gilmore I Covid-19 and alcohol—a dangerous cocktail BMJ 2020 369 m1987 10.1136/bmj.m1987 32434792 98. Butler MJ Barrientos RM The impact of nutrition on COVID-19 susceptibility and long-term consequences Brain Behav Immun 2020 87 53 54 10.1016/j.bbi.2020.04.040 32311498 99. Sallis R Young DR Tartof SY Sallis JF Sall J Li Q Physical inactivity is associated with a higher risk for severe COVID-19 outcomes: a study in 48 440 adult patients Br J Sports Med 2021 55 19 1099 1105 10.1136/bjsports-2021-104080 33849909 100. Travaglio M Yu Y Popovic R Selley L Leal NS Martins LM Links between air pollution and COVID-19 in England Environ Pollut 2021 268 115859 10.1016/j.envpol.2020.115859 33120349 101. Clark CE McDonagh STJ McManus RJ Martin U COVID-19 and hypertension: risks and management. A scientific statement on behalf of the British and Irish hypertension society J Human Hyper 2021 35 4 304 7 10.1038/s41371-020-00451-x 102. Gao M Piernas C Astbury NM Hippisley-Cox J O'Rahilly S Aveyard P Associations between body-mass index and COVID-19 severity in 6·9 million people in England: a prospective, community-based, cohort study Lancet Diabetes Endocrinol 2021 9 6 350 359 10.1016/S2213-8587(21)00089-9 33932335 103. Gibb R Redding DW Chin KQ Donnelly CA Blackburn TM Newbold T Zoonotic host diversity increases in human-dominated ecosystems Nature 2020 584 7821 398 402 10.1038/s41586-020-2562-8 32759999 104. Broom D. This is how we prevent future pandemics, say 22 leading scientists: World Economic Forum; 2020 [Available from: https://www.weforum.org/agenda/2020/11/covid-19-pandemics-nature-scientists/?utm_source=sfmc&utm_medium=email&utm_campaign=2737721_Agenda_weekly-4December2020&utm_term=&emailType=Newsletter. 105. Mays N Pope C Popay J Systematically reviewing qualitative and quantitative evidence to inform management and policy-making in the health field J Health Serv Res Policy 2005 10 Suppl 1 6 20 10.1258/1355819054308576 16053580 106. Strech D Tilburt J Value judgments in the analysis and synthesis of evidence J Clin Epidemiol 2008 61 6 521 524 10.1016/j.jclinepi.2008.01.001 18471654 107. Healthier Societies for Healthy Populations Group Healthier societies for healthy populations The Lancet 2020 395 10239 1747 1749 10.1016/S0140-6736(20)31039-4