• Reduction in patients undergoing following-haemodialysis, renal transplant, nonelective procedures
According to the objective of this systematic review the results described based upon the Impact of the COVID-19 Pandemic on the health care system in India on various parameters – number of outpatients, number of inpatients, number of patients undergoing minor and major surgeries, emergency trauma cases, patients undergoing nonurgent elective procedures.
From the seven included articles in this review, two articles described the disrupted oncology services in India by comparing these before and during the pandemic. A cohort study to describe the impact of COVID-19 on cancer care in India compared the oncology services provisions by cancer patients between 01 March 2020 and 01 March 2020 with similar duration for 2019 and concluded that there was a 54% reduction in new patient registration, 46% reduction in patient follow-up visit, 36% reduction in hospital admissions, 37% reduction in outpatient chemotherapy, 49% reduction in number of major surgeries, 52% reduction in minor surgeries, 23% reduction in patients accessing radiotherapy, 38% reduction in pathological diagnostic testing, 43% reduction in radiological diagnostic tests and 29% reduction in palliative care referrals. It also found that there was more reduction of oncology services for larger metro cities than smaller cities. 10 Another study, A retrospective analysis from western India determining the impact of the COVID-19 lockdown on Cancer care stated reduced patient visits and number of treatments received during the lockdown with chemotherapy being the most common treatment received. 11
Only one study out of the seven included studies described the impact of the COVID-19 pandemic on nephrology and transplant services at a tertiary care centre, in Ahmedabad, India. The study concluded that there was significant reduction in a number of outpatients and inpatients between April 2020 and June 2020 when compared with a similar duration in 2019 almost by 50%. There was also a reduction in donor transplants, haemodialysis and nonelective procedures such as renal biopsies and arteriovenous fistulas during March 2020. 12
Three out of seven included studies reported the impact of COVID-19 on ophthalmic care in India. A study conducted at a tertiary care ophthalmic institute in India reported a decrease of 97.14% in the routine patient visit, a decline of 35.25% in emergency outpatient visits, a decrease in routine and emergency ward admissions by 95.18% and 61.66% respectively, a reduction of elective surgeries by 98.18%, decrease of 58.81% in emergency surgeries, reduction of 99.61% in the number of donor corneas collected between 25 March 2020 and 15 July 2020 with comparison on previous year data of the same duration. 13 A study conducted in rural eye centres of Southern India reported that between 23 March 2020 and 19 April 2020, the total number of patients reduced during the lockdown-I period versus pre-lockdown. Only essential procedures were performed and most of the patients were treated for conjunctivitis. 14 A third study, which was conducted in a tertiary eye care Institute reported that there was a reduction in the number of patients presenting with ocular trauma in their emergency department during the lockdown as compared to the previous year. 15
A single epidemiology study out of seven studies included in this article, which was conducted at a tertiary care centre in New Delhi, explained various outcomes of the COVID-19 pandemic on the practice of orthopaedics and trauma through comparison between the pandemic period and pre-lockdown. It stated a reduction by 71.93% in outpatient attendance, a reduction of 59.35% in inpatient admissions, 55.78% reduction in surgical procedures including arthroplasty surgery, trauma and arthroscopic surgery during the pandemic period. 16
This study is being conducted to investigate the impact of the COVID-19 pandemic on the health care system in India by a systematic review approach based upon the eligibility criteria, seven articles related to the purpose of the study were screened after inclusion and the final analysis was prepared. The included studies defined various parameters – number of outpatients, number of inpatients, number of patients undergoing minor and major surgeries, emergency trauma cases, patients undergoing nonurgent elective procedures, follow-up visits for assessment of the impact of the COVID-19 pandemic on overstretched and overburdened health care system Of India. The studies included in this article reported that the COVID-19 pandemic has sharply affected the health care services in India including cancer care, nephrology services, ophthalmic care, trauma practice and orthopaedics care.
The COVID-19 Pandemic has led to a disrupted healthcare system which has subsequently impacted non-COVID disease conditions. The observed reduction in the number of new patient registrations, hospital registrations, major and minor surgeries, and transplant procedures as summarized in various studies during March 2020–April 2020 could be due to fear of infection among patients. The patients residing in rural parts of India found it difficult to access health services in metro cities due to travel restrictions during the lockdown period and this has led to delays in early screening, correct diagnosis and appropriate treatment which is of grave concern. These patients may present with advanced stages of the disease and create a backlog of patients by overloading the healthcare system.
Hospitals faced certain challenges that inhibited them from providing appropriate care to the patient such as- many hospitals being converted to COVID-19 dedicated treatment facilities and as result, they faced a widespread shortage of Personal Protective Equipment (PPE) supplies. Hospitals reported a shortage of adequate staff as they were themselves exposed to the virus. Various hospitals reported lack of necessary medical equipments such as ICU beds and Ventilators which was a major threat.
Despite the lockdown and various challenges encountered, hospitals realized the need of improving the accessibility of healthcare through teleconsultation along with in-person visits during these challenging times. In the absence of direct consultations to the patients, telemedicine was conducted to address the concerns of outpatients and therefore, reduce their need to visit the hospital.
In general, the COVID-19 Pandemic has posed a serious threat to all aspects of the healthcare system in India by affecting the activities of hospitals that provide treatment services to patients for non-COVID-19 diseases.
The results of this study show that Indian Healthcare System during the COVID-19 pandemic has suffered serious challenges, which can be a wake-up call because due to delayed diagnosis, a large number of patients will present with advanced stages of the non- covid-19 disease such as cancers, which may require emergency treatment. Strengthening of the Indian healthcare system is required so that it does not crumble under future pandemics if any. Need of the hour is a robust healthcare model and effective healthcare policies with regular updates to manage the current pandemic along with more emphasis on telemedicine as this is not the last pandemic that India will face. In conclusion, the COVID-19 pandemic has significantly impacted the healthcare system in India.
Limitations of the study: This study has limitation regarding language inclusion, as the researchers’ proficiency was limited to English, resulting in the exclusion of articles written in other languages. Another major limitation is the bias as the he papers relies on available online published studies in high-quality journals, which may introduce a bias towards studies that have been published and accessible. There may be relevant studies that have not been included in the review, potentially leading to a skewed representation of the impact of COVID-19 on the healthcare system in India.
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding: The author(s) received no financial support for the research, authorship, and/or publication of this article.
Ethical statement: No Ethical approval is needed.
The 4 case studies by Penn Nursing illustrate how nurses can be really powerful collaborators and generators of solutions within Healthcare. The videos describe the main attributes that nurses bring to the problem solving table
Visit Penn Nursing website Design Thinking for Health to watch videos on the following case studies
For a full index of all The Design Thinking Association articles on Design Thinking in Healthcare, visit our vertical markets - Healthcare page .
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International Journal of Quality & Reliability Management
ISSN : 0265-671X
Article publication date: 2 October 2019
The purpose of this paper is to explore the voice of the customer, key performance indicators, critical to quality characteristics, critical success factors, and commonly used tools and techniques for deploying the Lean Six Sigma (LSS) strategy in Indian private hospitals, with special attention to the medical records.
The study utilizes the action research methodology to obtain a greater understanding of the use of LSS in the Indian healthcare sector. Multiple case studies were designed and successfully deployed to understand and ascertain challenges in LSS implementation. Five case studies were carried out in the Medical Records Departments (MRD) of four private hospitals in India.
Patients perceive that waiting in queue harms their health, which can be rectified by addressing the cycle time of the system. The research also found that effective leadership, availability of data, involvement of cross-functional team and effective communication are critical to the success of LSS projects. In addition, control charts, cause and effect diagram, 5S, gemba, two-sample t -test, standardization, waste analysis and value stream mapping are some of the common tools used to improve healthcare systems.
The research was restricted to studying the impact of LSS on the workflow and resource consumption of the MRD in Indian allopathic hospitals only. The validity of the results can be improved by including more hospitals and more case studies from the healthcare sector in different countries.
The findings will enable researchers, academicians and practitioners to incorporate the results of the study in LSS implementation within the healthcare system to increase the likelihood of successful deployment. This will provide greater stimulus across other departments in the hospital sector for wider and broader application of LSS for creating and sustaining process improvements.
Bhat, S. , Antony, J. , Gijo, E.V. and Cudney, E.A. (2020), "Lean Six Sigma for the healthcare sector: a multiple case study analysis from the Indian context", International Journal of Quality & Reliability Management , Vol. 37 No. 1, pp. 90-111. https://doi.org/10.1108/IJQRM-07-2018-0193
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The healthcare industry is an ever-evolving field with innovations and improvements happening daily. As healthcare providers strive to deliver the best care possible, case studies have become a valuable resource for learning and growth. In this article, we will explore various case studies in healthcare, highlighting both success stories and the lessons learned along the way. By analyzing what works and why, we can gain insight into the practices that lead to triumphs in healthcare and potentially replicate these successes in our own organizations.
Healthcare case studies provide a unique opportunity to dissect real-world scenarios, understand the decisions made, and measure the outcomes of those choices. One notable success story is the implementation of telemedicine in rural areas. By leveraging technology, healthcare providers have successfully expanded access to care for patients who would otherwise have to travel long distances for treatment. Lessons learned include the importance of investing in reliable technology and training staff to effectively use telemedicine platforms.
Another critical case study involves the management of electronic health records (EHRs). When a large hospital system transitioned to a new EHR system, they faced significant resistance from physicians who were accustomed to the old way of doing things. However, by involving physicians in the planning and implementation process, the hospital successfully integrated the new system, leading to improved efficiency and patient care. This case study highlights the value of stakeholder engagement and effective change management.
In the fight against infectious diseases, case studies have shown the significance of swift and coordinated responses. An example of this is the containment of Ebola in West Africa. Through international collaboration and the rapid deployment of healthcare resources, the spread of the virus was effectively limited. This case study underscores the importance of preparedness, communication, and teamwork in tackling healthcare crises.
Understanding why certain strategies succeed is crucial for replicating positive results in the healthcare industry. For instance, one hospital’s initiative to reduce patient readmissions focused on comprehensive discharge planning and follow-up care. By ensuring patients had clear instructions and support after leaving the hospital, readmission rates dropped significantly. This case study emphasizes the role of thorough patient education and post-discharge care in improving outcomes.
In the realm of preventive care, a primary care clinic introduced a program to increase vaccination rates among its patient population. By actively reaching out to patients due for immunizations and offering flexible scheduling options, the clinic saw a dramatic increase in vaccination rates. The takeaway from this case study is the impact of proactive patient engagement and removing barriers to care.
Lastly, a healthcare organization’s embrace of continuous quality improvement (CQI) led to enhanced patient safety and satisfaction. By fostering a culture of open communication and ongoing learning, the organization identified areas for improvement and systematically implemented changes. This case study demonstrates the power of a commitment to CQI as a driver for excellence in healthcare.
The healthcare industry is rich with case studies that provide valuable insights and lessons learned. By analyzing and understanding these success stories, healthcare providers can apply similar strategies to achieve positive outcomes in their own organizations. Whether it’s through technology, stakeholder engagement, or quality improvement initiatives, these case studies offer a blueprint for triumph and provide a roadmap for future success in the ever-changing landscape of healthcare.
Case studies are valuable as they offer real-world examples of challenges and solutions in healthcare. They provide insights into successful decision-making, problem-solving, and strategies that can be applied by healthcare professionals and organizations facing similar scenarios.
The article discusses the criteria for selecting case studies, such as their impact on healthcare outcomes, innovation, or overcoming significant challenges. It highlights the diversity of cases to ensure relevance to a broad audience, considering different healthcare settings, specialties, and contexts.
Certainly! Examples may include cases where innovative technologies improved patient outcomes, or instances where strategic decisions enhanced operational efficiency. The article presents these stories to illustrate valuable lessons learned and best practices that readers can apply in their own healthcare settings.
The article explores how case studies offer learning opportunities, allowing healthcare professionals to gain insights from others’ experiences. Organizations can leverage these stories for staff training, fostering a culture of continuous improvement and encouraging employees to apply lessons learned to their daily practices.
The article offers recommendations based on the case studies, such as the importance of collaboration, data-driven decision-making, and embracing innovation. It provides actionable insights that healthcare leaders can use to inform their decision-making processes and drive positive outcomes within their organizations.
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Human Resources for Health volume 22 , Article number: 61 ( 2024 ) Cite this article
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Kenya grapples with a paradox; severe public sector workforce shortages co-exist with rising unemployment among healthcare professionals. Medical schools have increased trainee outputs, but only 45% of newly qualified/registered doctors were absorbed by the public sector during 2015–2018. In such a context, we explore what influences doctors’ career choices at labour market entry, specifically understanding the role of public service motivation (PSM).
We conducted a cross-sectional and prospective study of interns and recently graduated doctors to examine PSM, their intention to work in the public sector and their final employment sector and status. We surveyed them on their PSM and job intentions and conducted a prospective follow-up survey of the interns, around one year later, to understand their employment status.
We recruited 356 baseline participants and followed up 76 out of 129 eligible interns. The overall PSM score was high among all participants (rated 4.50/5.00) irrespective of sector preferences. 48% (171/356) of the participants preferred to work in the public sector immediately after internship, alongside 16% (57/356) preferring direct entry into specialist training—commonly in the public sector. Only 13% (46/356) and 7% (25/365) preferred to work in the private or faith-based sector. Despite the high proportion of interns preferring public sector jobs, only 17% (13/76) were employed in the public sector at follow-up and 13% (10/76) were unemployed, due to lack of job availability.
High PSM scores irrespective of sector preferences suggest that doctors are generally committed to serving the ‘public good’. Many intended to work in the public sector but were unable to due to lack of job opportunities. Policymakers have an opportunity to tackle workforce gaps in the public sector as young doctors continue to express a preference for such work. To do this they should prioritise creating adequate and sustainable job opportunities.
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Public administration scholars have long been inquiring about what motivates people to join/work for the public sector and the value of this motivation to public organisations. Perry and Wise (1990) introduced the concept of public service motivation (PSM), which they defined as “an individual’s predisposition to respond to motives grounded primarily or uniquely in public institutions and organizations” [ 1 ]. Perry also later developed a PSM measure from a US population sample which includes four conceptual dimensions of PSM: attraction to public policy making, commitment to public interest, compassion, and self-sacrifice [ 2 ]. The critique of Perry’s scale over its cross-cultural and international application led to a revision of the scale by Kim and colleagues, who adapted the PSM dimensions and the measure to make it suitable across diverse cultures and languages [ 3 ].
Work examining PSM has consistently demonstrated the consequences of PSM in relationship to person–organisation fit, job satisfaction, commitment [ 4 , 5 , 6 ], and retention. Studies have also focused on whether PSM is associated with individuals’ sector choices, and whether PSM could form the basis of recruiting candidates for public organisations [ 7 , 8 ]. A number of studies have established that measures of PSM among public servants are greater than for those working in private organisations [ 6 , 9 ]. Other studies have examined whether PSM exists prior to job entry and whether it could predict public sector preference [ 4 , 9 , 10 , 11 , 12 ]. However, PSM has only been studied in a narrow range of national contexts, mostly in high-income countries, and very few studies have used Kim’s PSM scale, especially in low- and middle-income country (LMIC) settings. Our study therefore extends PSM research by using Kim’s scale, and investigating its association with the career decisions of Kenyan medical doctors who are in their internship and expected, after one year, to transition to independent clinical practice as fully licensed medical practitioners. We suggest this pre-licensure phase is critical in shaping individuals’ career trajectories, and of great interest considering the workforce shortages of medical doctors, especially in the public sector in LMIC contexts.
The public sector provides the largest share of healthcare in Kenya. Approximately 46% of health facilities are run by the government in 2022, 44% by the private sector and the rest by faith-based and non-governmental organisations [ 13 ]. However, the public sector provides a greater proportion of inpatient hospital care, particularly to the poor and those in rural areas [ 14 ], as the costs of utilising public hospital services are lower. Additionally, a large number of private sector facilities are small clinics and dispensaries [ 15 ].
Kenya grapples with a shortage of medical workforce, with an estimated density of 0.23 per 1000 population in 2020. This is significantly lower than the average for LMICs (1.4 per 1000 in 2017) [ 16 ]. Medical doctors are typically trained in universities through a Bachelor of Medicine & Bachelor of Surgery (MBChB) programme that lasts six years with an additional internship year. As with other African countries, medical schools in Kenya are expanding to meet health workforce gaps. Now 11 medical schools are providing undergraduate medical training with a combined annual output of 628 in 2019 [ 17 ], nearly double that of only a few years previously (287 in 2006, 320 in 2016) [ 18 , 19 , 20 ].
Before 2013, when Kenya devolved responsibility for health systems to 47 semi-autonomous county governments, medical doctors were automatically employed and deployed by the national government after their internship. Since devolution, counties have managed health workforce recruitment and management [ 21 , 22 ], and automatic employment of medical doctors post-internship ended. This means that medical doctors now must apply for jobs after internship, but whether they are employed is contingent on vacancies advertised by county/national government(s) and other organisations. Most doctors who completed their internship would initially be employed as medical doctors in public, private or faith-based health facilities. Public sector roles in the Ministry of Health or County Health Department or parastatal organisations typically require some prior working experience with entry into specialist training also requiring 2–3 years’ work experience.
Recent data from the Kenyan Ministry of Health suggested between 2015 and 2018, only 45% (825/1,800) of newly qualified and registered doctors were employed in the public sector [ 19 ]. Such low absorption could be due to the lack of job opportunities provided by governments (“demand side”) [ 23 ], or medical doctors’ preferring alternatives to public sector jobs (“supply side”), potentially due to the poor conditions they face as interns in public hospitals [ 24 ]. Understanding what influences medical doctors’ employment choices is crucial for shaping effective healthcare policies and workforce planning, especially as the majority of hospital care provided to the population is still through the public sector [ 14 ]. Several studies in Kenya have investigated healthcare professionals’ public sector preferences [ 25 , 26 ]. However, to the best of our knowledge, no previous study has examined the concept of PSM and its relations with Kenyan medical interns’ career preferences. Our study fills this gap.
We used a combined cross-sectional and a prospective study design to examine PSM, intention to work in the public sector and final employment sector among medical interns and recently graduated medical doctors in Kenya. This study is embedded in a larger project that focuses on the internship training experiences of Kenyan doctors [ 24 ].
From Nov 2021 to May 2022, we conducted a cross-sectional survey of Kenyan medical interns and medical doctors who completed their internship within 3 years. We used a mix of convenience and snowball sampling approaches [ 27 ] to include survey participants. We worked with different stakeholders and asked them to share the survey through their respective platforms such as WhatsApp or short message service (SMS). Our approach included working with (a) the Kenyan Medical Practitioners and Dentists Council, which shared the survey with all eligible medical officers on their registry through SMS; (b) the Kenya Medical Association Young Doctor Network and Kenya Young Doctor Caucus that shared within their respective WhatsApp groups; (c) three major medical schools based in or near Nairobi that shared within recent graduate class representative; and (d) selected facilities in the Clinical Information Network operated by KEMRI-Wellcome Trust Research Programme [ 28 , 29 ], which shared the survey within facilities’ own WhatsApp groups. The survey was online and self-administered through REDCap, and one GB of data (worth 250 KES or 1.8 GBP) were given to respondents who fully completed the survey. Out of an estimated 2,400 eligible participants (estimated 600 graduates per year), 498 started the survey and 356 fully completed the survey and so were included for analysis. Out of the 356 sample, 227 were medical doctors who completed their internship within 3 years and 129 were current interns.
The cross-sectional survey questionnaire focuses on PSM and public sector intention. It includes questions on (1) demographics and medical training (name of medical school and internship hospital as well as funding for medical training); (2) preferred job roles immediately after internship and five years after internship (one of seven options listed in Table 3 , or others). Medical doctors who had already completed internship and were already in the labour market were required to indicate the year of internship completion, and what was their most preferred option when they finished internship; and (3) PSM evaluation using the scale developed by Kim et al. [ 3 ]. The scale has 16 items grouped into four factors and domains, i.e. attraction to public participation, commitment to public values, compassion, and self-sacrifice. The questionnaire was developed as part of a broader medical internship experience project and questions were pre-tested including the use of cognitive interviews [ 30 , 31 ] to ensure that all questions were relevant and that respondents could fully understand the questions.
We further conducted a prospective telephone follow-up of the 129 medical interns from March to May 2023, around one year later, to understand their final employment status. We only followed up participants who had consented to a follow-up interview at baseline, and who provided us with their phone numbers. The follow-up survey included five questions on their current role, locations, employment terms, and also an open-ended question on reasons for current employment.
Data were managed and analysed using STATA (Stata V.17). Descriptive statistics on frequencies, percentages and means were used to describe the demographics, PSM and public sector intention of all baseline participants as well as and final employment status of follow-up participants. For example, we calculated the mean score (out of 5) across four PSM domains and the aggregated PSM score. We also conducted a confirmatory factor analysis to examine the performance of PSM in the sample and the degree to which items are related to the underlying dimension as proposed by Kim et al. [ 3 ].
Ethical approval for the study is issued by Oxford Tropical Research Ethics Committee (OxTREC 563-20 and OxTREC 518-21) and Kenya Medical Research Institute (KEMRI) (SERU 4071). Electronic consents or written consents were obtained for all survey participants.
Basic sociodemographic and medical training characteristics of baseline participants are presented in Table 1 . 36% (129/356) of the survey population were interns at the time of the survey, having completed 6.5 months of internship training on average; the rest were post-internship doctors that mostly completed their internship from 2020 to 2022. The University of Nairobi contributed to 57% (201/356) of the survey population, it is also the largest medical school in Kenya graduating nearly half of the doctors. Most participants undertook their internship in public facilities (78%, 276/356), whereas 73% of internship training centres are public hospitals [ 32 ]. As for follow-up, 116 out of 129 interns agreed to be followed up through telephone calls. We successfully followed up 77 of them with complete data (66%). The time from baseline to follow-up is on average 14 months.
As shown in Table 2 in the item- and factor-specific means. Self-sacrifice, which is the foundational concept representing the altruistic or pro-social origins of PSM, was rated slightly lower in our sample (factor mean 3.88 out of 5). For example, Q16 “I would agree to a good plan to make a better life for the poor, even if it costs me money” was rated 4.04 out of 5. Nonetheless, despite overall lower average compared to other domains, some factors under self-sacrifice, i.e. Q13 “I am prepared to make sacrifices for the good of society” were rated quite highly indicating substantial commitment and inherent value to serving public good being integral to medical doctors’ professional identity and could therefore explain the overall high PSM among medical doctors. Other factors and the overall PSM score (4.50 out of 5) were relatively high, suggesting that most respondents had high motivation for public service. Also shown in Additional fle 1 , older participants and those who received scholarships during medical training had higher PSM scores.
Indices of the PSM developed by Kim et al. [ 3 ], which has not been previously tested in the Kenyan sample, showed a moderate fit according to the confirmatory factor analysis (comparative fit index [CFI] = 0.92, root mean square error of approximation [RMSEA] = 0.08, standardised root mean squared residual [SRMR] = 0.06). When removing item Q2, as Kim and colleagues suggest [ 33 ], there was a slight improvement in RMSEA but still a moderate fit. The reliability coefficient (Cronbach’s alpha) for the overall scale was 0.88 and the coefficients for the four factors ranged from 0.76 to 0.88 (Table 2 ).
Baseline participants ( n = 356) were asked about their preferred job roles immediately after internship and five years after internship (Table 3 ). Most participants (48%, 171/356) stated a preference to work in the public sector as medical doctors immediately after internship, followed by direct entry into specialist training (16%, 57/356)—which is also predominantly undertaken in the public sector. Preference for entry into the private sector (13%, 46/356) or faith-based sector (7%, 27/356) immediately after internship were low. As for job sector preference five years after internship, low preference for the private and faith-based sectors (10%, 36/356 and 4%, 14/356) persisted. At 5 years slightly fewer respondents intended to remain working in the public sector (21%, 75/356) and more stated a preference to go into specialist medical training (42%, 150/356). These trends are similar between the 129 interns and the post-internship doctors (Table 4 ).
We also compared PSM scores between baseline participants with different career intentions (Additional File 2 ). We found that participants with different intentions for career sector all had high PSM with minimal variations. For example, those who preferred to work in the public sector as medical doctors had an average PSM score of 4.45 out of 5, whereas those preferring to work in the private sector and faith-based sector had scores of 4.53 and 4.70 out of 5, respectively. Therefore, our findings suggest that PSM is not a useful discriminator for career intention, but instead other factors such as pay and working arrangement might influence career intention more.
Table 4 presents the career intention and final employment of medical interns. Out of 129 interns recruited at baseline, we successfully followed up 76 participants who completed their internship and hereby focused on these participants. While 49% (37/76) of these participants indicated intention to work in the public sector as medical doctors at baseline, only 17% (13/76) indicated actual employment in the public sector one year after internship. Most respondents (65%, 49/76) ended up working in the private sector or faith-based hospitals despite not being the preferred job choice. Around one year after internship, no respondents were employed in the Ministry of Health/County Health Department or parastatal organisations, not-for-profit technical assistance organisations or enrolled in specialist trainings.
Additionally, 13% (10/76) of respondents suggested that they were unemployed at the time of follow-up. Of those who were employed, only 8% (5/66) were employed on a permanent contract, and more commonly they were employed on contract (52%, 34/66) or on a locum basis (41%, 27/66) especially for private-sector jobs. When asked reasons for choosing their current employment as an open-ended question, nearly 60% of respondents stated that these were the only available jobs for them, oftentimes only temporary job contracts available in private sectors.
Our cross-sectional and prospective study of Kenyan medical doctors and interns provided insights into their PSM, intention to work for the public sector and their final employment. Our findings show that the majority of the respondents generally had high motivation for public service. Most (48%) respondents stated a preference to work as medical doctors in the public sector, rather than the private or faith-based sector immediately after internship, but only 17% indicated actual employment in the public sector at one-year follow-up, with 65% working in private health care, and 13% unemployed.
There were also minimal variations between their PSM scores, which suggests that public sector job preference is not linked to PSM. We found that while all the other items/domains of PSM were rated high, the pro-social aspect of PSM, i.e. self-sacrifice, was rated relatively lower among the respondents. These findings are similar to Harris et al.’s study of Ugandan public servants, where Kim et al.’s scale suggested an overall high public service, commitment to public values, and compassion, and low willingness to self-sacrifice in favour of the common good [ 34 ]. Some studies reported that self-sacrifice is the most impactful and stable PSM dimension and is associated with a preference for public sector employment [ 35 ]. However, a recent review of PSM literature in Africa highlighted contradictory findings regarding the linkage between self-sacrifice and inclination towards public service, highlighting the possible differences in culture and value that could explain PSM and motives [ 6 ].
The minimal variations of PSM between participants with different career intentions also suggested that PSM is measuring a set of attitudes towards ‘public service’, not necessarily ‘public sector’ [ 36 ]. The concept of public sector could be interpreted differently in different cultures and settings [ 37 ]. In the Kenyan setting, working in faith-based not-for-profit organisations could also be considered as working for the ‘semi-public sector’. Because a medical doctor’s job is serving people and saving lives, regardless of the sectors they work, all respondents may believe they were working in the public interest and helping society. Our findings therefore indicated that PSM might not be the primary reason for the low absorption of medical doctors into the public sector in the Kenyan setting.
As noted, nearly half of the medical doctors surveyed indicated intention to work in public hospitals immediately after internship, but only 17% were employed in the public sector at follow-up. This finding is similar to previous qualitative work with medical doctors in Kenya and Uganda [ 23 , 38 ]. The preference for the public sector could be due to various reasons beyond PSM and ‘serving the public’. For example, this may be due to better pay and job security, the public sector being “easier to work in” or linked enabling with dual practices, and culturally ingrained appreciation for public sector jobs [ 38 , 39 , 40 ]. In comparison, jobs in the private sector were perceived to have poorer contractual terms and involve higher workloads in the Kenyan setting. This contrasts with high-income settings, where private medical work is better paid [ 23 , 38 ].
Kenya has boosted its supply of medical professionals through the expansion of medical training, although this has still not yet reached the country’s goal listed under its norms and standards [ 20 ]. However, demand for public sector doctors has increased more slowly, despite a shortage of doctors in the public sector. This is mostly due to the lack of sustained financial commitments for the health workforce and preference for other healthcare cadres [ 23 ]. Consequently, despite public sector preference many doctors remain unemployed, underemployed, or work in the private sector, often on temporary contracts, [ 23 , 38 ]. Many doctors “just want a job anywhere (they) could find”, even if it is not the role they would have ideally chosen [ 38 ].
The findings of this study have implications for policy and practice. First on the positive side, our data support evidence that, for certain professions, the nature of the job serves some public good and therefore is perceived as ‘public service’, as evidenced by the high PSM scores regardless of sector preference. Given this, policymakers and healthcare managers therefore need to worry less about medical doctors’ public service values and motivations, but need to remain attentive to other factors that might influence doctors' career choices, satisfaction and retention.
Second, considering the mismatch between public sector intention and employment of doctors, and the high level of health worker unemployment, Kenya needs to prioritise workforce planning. This proactive approach could ensure that the training and development of medical doctors is aligned with national healthcare needs and employment capacities, therefore reducing the risk of unemployment among newly trained doctors. Additionally, many African countries have been conducting health labour market analysis [ 20 , 41 ] and there exists an opportunity to integrate PSM into this analysis to better contextualise planning efforts as well as inform recruitment, retention, and motivation of healthcare workers. Significantly, LMICs need to re-think the causes of health workforce shortages in the public sector, as many are witnessing growing health workforce underutilisation and unemployment [ 42 ]. More in-depth, country-specific research evidence on the supply/demand mismatch dilemma is needed to draw policymakers’ attention to this issue.
Finally, our study adds to the global PSM literature by first using the PSM scale developed by Kim et al. in the Kenyan healthcare setting [ 3 ]. While Kim et al.’s scale was developed in 2013, with an international sample across 12 countries in response to criticisms of the American focus of the scale developed by Perry in 1996 [ 2 ], the majority of PSM scholarship still largely used the Perry scale when measuring PSM [ 4 , 6 , 43 ]. The use of Kim et al.’s scale is still limited in LMICs especially African countries, and many studies did not report on its psychometric performances. One exception is the work by Mikkelsen and colleagues which tested Kim et al. scale in four world regions including three countries in Africa (Ghana, Malawi and Uganda). Mikkelsen and colleagues suggested the scale’s partial metric invariance and scale non-invariance, i.e. causes and consequences of PSM are comparable across most countries but not means and its dimension. Our study suggested a moderate-to-good fit according to the confirmatory factor analysis and reliability coefficient, future studies should consider testing the scale’s performance in different populations and contexts.
There are some limitations that should be considered when interpreting our results. First, this work was conducted during the Covid-19 pandemic, which presented logistics challenges for data collection. We therefore used a mix of convenience and snowballing approaches to sample baseline respondents. The 356 responses came from all medical schools and 65 out of 74 internship hospitals. The sample is roughly 15% of the eligible population but not representative. Covid-19 might have also impacted the broad labour market dynamic. For example, high PSM among study participants and financial constraints of the government.
Second, at baseline, we included respondents who were interns and also those who already completed internships. While data in Appendix 1 suggested no significant differences between these participants, we acknowledge that responses from post-internship medical doctors could be subject to recall biases. Furthermore, we also did not survey these graduated doctors of their current sector of employment, and further comparing PSM scores between doctors in different sectors could help us further understand the role of PSM.
Third, while the risk of loss to follow-up is low considering the similar trends of job intention between baseline and follow-up intern respondents (Table 4 ), it is possible that people who did not respond to our baseline survey had different career intentions and employment outcomes. Moreover, we were only able to follow up interns on average 14 months after internship, and their career outcomes may be changing due to the emerging labour market dynamic in Kenya. Nonetheless, we still believe it provided a good description of the medical doctor and intern population.
Finally, we also acknowledge our self-administered survey, including PSM could be influenced by social desirability biases. This might be true for the relatively lower self-sacrifice domain. Considering the possible differences in culture and value that explain PSM but also respondents’ response patterns, future studies should continue testing PSM in diverse populations and contexts.
We investigated PSM, public sector employment intention, and the actual employment of Kenyan medical doctors and interns. Our study found high scores of PSM among doctors irrespective of their sector preferences. These findings indicated an innate desire to serve the public good as a common trait among medical doctors in Kenya. PSM was not necessarily linked with sector preference due to contextual factors such as job stability and better pay which attracted medical doctors to public sector jobs. Many doctors stated their intention to work in the public sector but few were able to do so, due to a lack of job opportunities. Policymakers should focus on creating job opportunities to ensure medical doctors are recruited and retained in the public sector.
The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.
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This work is supported by an Africa Oxford travel grant (AfOx-209). YZ is supported by the University of Oxford Clarendon Fund Scholarship, an Oxford Travel Abroad Bursary and a Keble Association grant. DG and ME are supported by the National Institute for Health Research, Learning to Harness Innovation in Global Health for Quality Care (HIGH-Q) using UK aid from the UK Government to support global health research [NIHR130812]. ME is supported by a Wellcome Trust Senior Research Fellowship (#207522). CN receives funding from the Economic and Social Research Council [grant number ES/T008415/1]. National Institute for Health Research Applied Research Collaboration Oxford and Thames Valley at Oxford Health NHS Foundation Trust. Consortium iNEST (Interconnected North-Est Innovation Ecosystem) funded by the European Union NextGenerationEU (Piano Nazionale di Ripresa e Resilienza (PNRR)—Missione 4 Componente 2, Investimento 1.5—D.D. 1058 23/06/2022, ECS_00000043). The views expressed in this publication are those of the author(s) and not necessarily those of the NIHR or the UK government.
Daniel Mbuthia and Yingxi Zhao contributed equally to this manuscript as joint first authors.
KEMRI-Wellcome Trust Research Programme, Nairobi, Kenya
Daniel Mbuthia, David Gathara, Jacinta Nzinga & Mike English
NDM Centre for Global Health Research, Nuffield Department of Medicine, University of Oxford, S Parks Rd, Oxford, OX1 3SY, UK
Yingxi Zhao & Mike English
MARCH Centre, London School of Hygiene and Tropical Medicine, London, UK
David Gathara
Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
Catia Nicodemo
Department of Economics, Verona University, Verona, Italy
King’s Business School, King’s College London, London, UK
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DM, YZ, DG, CN, JN and ME designed the study. DM and YZ contributed to data collections. YZ conducted analysis. DM and YZ wrote the first draft of the manuscript. All authors provided critical feedback on the first draft of the manuscript, read and approved the final manuscript.
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Mbuthia, D., Zhao, Y., Gathara, D. et al. Public service motivation, public sector preference and employment of Kenyan medical doctor interns: a cross-sectional and prospective study. Hum Resour Health 22 , 61 (2024). https://doi.org/10.1186/s12960-024-00945-6
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Health officials, development partners, and experts met this week to strategize scaling up of innovations to improve quality integrated primary health care at a Regional Workshop here. Participants reviewed successful models from across the WHO South-East Asia Region, specifically explored innovations related to National PHC Integration in Indonesia, and collectively identified steps forward for improving both quality and integration in healthcare delivery.
“Poor quality care is today, a greater barrier to reducing mortality in low-and middle-income countries than insufficient access,” said Saima Wazed, Regional Director, WHO South-East Asia, in her inaugural address at the ‘Regional Workshop on Innovations for Quality Integrated Primary Health Care.’ She emphasized that as a key aspect of quality, the integration of primary health services is crucial for providing seamless care throughout an individual’s life.
“Integration through ensuring service continuity and people-centredness is a key determinant of quality,” the Regional Director added.
(Photo credit: WHO Indonesia)
The World Health Organization is urging countries in the WHO South-East Asia Region to expand the adoption of cutting-edge policies, practices, and technologies that provide comprehensive, quality care throughout all stages of life. This call-to-action highlights successful models from across the Region, aimed at tackling the increasing challenges of noncommunicable diseases (NCDs), mental health, public health emergencies, and climate effects alongside traditional priorities in service delivery.
The WHO South-East Asia Region has long recognized primary health care as the foundation of robust health systems and broader development goals. In 2023, health ministers from the Region reaffirmed their commitment to prioritizing investments in primary health care. The South-East Asia Region Primary Health Care Strategy 2022-2030 outlines key actions to transform health systems through a primary health care approach.
The recently launched WHO South-East Asia Regional Roadmap for Results and Resilience, underscores WHO’s commitment to building a learning health system that prioritises innovations, equity, and sustainability . The holistic approach aims to ensure health and well-being for all in a comprehensive manner. With WHO serving as a key enabler , the roadmap seeks to forge partnerships across governments, development agencies, philanthropic organizations, academia, the private sector, and civil society to achieve universal health coverage.
According to the Lancet Commission, nearly 60% of the 8.6 million annual deaths from treatable conditions are linked to poor quality care. During the COVID-19 pandemic, the lack of integration of public health functions in primary health care posed a significant bottleneck, in prevention, preparedness, and response. It also underscored the urgent need to strengthen primary health care systems while integrating essential public health functions in the Region for better preparedness and resilience against future health crises.
Addressing the diverse challenges in delivering quality integrated primary health care to the Region’s two billion people, the Regional Director said, “We stand at a historic moment in time. A remarkable transformation is taking place across our countries in our Region: a transformation from a focus on a few select diseases to that of the full human condition, across the life course.”A compilation of “Positive Practice Case Stories” was launched, featuring a set of 20 case studies from across the Region that highlight innovative approaches and solutions in various countries.
“My vision for our Region is where people have access to quality healthcare, regardless of where they live, and regardless of their income or social status. I would like us to be a Region which takes a holistic approach to health and well-being; where people are empowered - both physically and mentally - to achieve their full potential. I would like to shape a Region which cares for all and strengthens and protects the most vulnerable who live in it.” the Regional Director said.
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Climate warming disproportionately impacts countries in the Global South by increasing extreme heat exposure. However, geographic disparities in adaptation capacity are unclear. Here, we assess global inequality in green spaces, which urban residents critically rely on to mitigate outdoor heat stress. We use remote sensing data to quantify daytime cooling by urban greenery in the warm seasons across the ~500 largest cities globally. We show a striking contrast, with Global South cities having ~70% of the cooling capacity of cities in the Global North (2.5 ± 1.0 °C vs. 3.6 ± 1.7 °C). A similar gap occurs for the cooling adaptation benefits received by an average resident in these cities (2.2 ± 0.9 °C vs. 3.4 ± 1.7 °C). This cooling adaptation inequality is due to discrepancies in green space quantity and quality between cities in the Global North and South, shaped by socioeconomic and natural factors. Our analyses further suggest a vast potential for enhancing cooling adaptation while reducing global inequality.
Introduction.
Heat extremes are projected to be substantially intensified by global warming 1 , 2 , imposing a major threat to human mortality and morbidity in the coming decades 3 , 4 , 5 , 6 . This threat is particularly concerning as a majority of people now live in cities 7 , including those cities suffering some of the hottest climate extremes. Cities face two forms of warming: warming due to climate change and warming due to the urban heat island effect 8 , 9 , 10 . These two forms of warming have the potential to be additive, or even multiplicative. Climate change in itself is projected to result in rising maximum temperatures above 50 °C for a considerable fraction of the world if 2 °C global warming is exceeded 2 ; the urban heat island effect will cause up to >10 °C additional (surface) warming 11 . Exposures to temperatures above 35 °C with high humidity or above 40 °C with low humidity can lead to lethal heat stress for humans 12 . Even before such lethal temperatures are reached, worker productivity 13 and general health and well-being 14 can suffer. Heat extremes are especially risky for people living in the Global South 15 , 16 due to warmer climates at low latitudes. Climate models project that the lethal temperature thresholds will be exceeded with increasing frequencies and durations, and such extreme conditions will be concentrated in low-latitude regions 17 , 18 , 19 . These low-latitude regions overlap with the major parts of the Global South where population densities are already high and where population growth rates are also high. Consequently, the number of people exposed to extreme heat will likely increase even further, all things being equal 16 , 20 . That population growth will be accompanied by expanded urbanization and intensified urban heat island effects 21 , 22 , potentially exacerbating future Global North-Global South heat stress exposure inequalities.
Fortunately, we know that heat stress can be buffered, in part, by urban vegetation 23 . Urban green spaces, and especially urban forests, have proven an effective means through which to ameliorate heat stress through shading 24 , 25 and transpirational cooling 26 , 27 . The buffering effect of urban green spaces is influenced by their area (relative to the area of the city) and their spatial configuration 28 . In this context, green spaces become a kind of infrastructure that can and should be actively managed. At broad spatial scales, the effect of this urban green infrastructure is also mediated by differences among regions, whether in their background climate 29 , composition of green spaces 30 , or other factors 31 , 32 , 33 , 34 . The geographic patterns of the buffering effects of green spaces, whether due to geographic patterns in their areal extent or region-specific effects, have so far been poorly characterized.
On their own, the effects of climate change and urban heat islands on human health are likely to become severe. However, these effects will become even worse if they fall disproportionately in cities or countries with less economic ability to invest in green space 35 or in other forms of cooling 36 , 37 . A number of studies have now documented the so-called ‘luxury effect,’ wherein lower-income parts of cities tend to have less green space and, as a result, reduced biodiversity 38 , 39 . Where the luxury effect exists, green space and its benefits become, in essence, a luxury good 40 . If the luxury effect holds among cities, and lower-income cities also have smaller green spaces, the Global South may have the least potential to mitigate the combined effects of climate warming and urban heat islands, leading to exacerbated and rising inequalities in heat exposure 41 .
Here, we assess the global inequalities in the cooling capability of existing urban green infrastructure across urban areas worldwide. To this end, we use remotely sensed data to quantify three key variables, i.e., (1) cooling efficiency, (2) cooling capacity, and (3) cooling benefit of existing urban green infrastructure for ~500 major cities across the world. Urban green infrastructure and temperature are generally negatively and relatively linearly correlated at landscape scales, i.e., higher quantities of urban green infrastructure yield lower temperatures 42 , 43 . Cooling efficiency is widely used as a measure of the extent to which a given proportional increase in the area of urban green infrastructure leads to a decrease in temperature, i.e., the slope of the urban green infrastructure-temperature relationship 42 , 44 , 45 (see Methods for details). This simple metric allows quantifying the quality of urban green infrastructure in terms of ameliorating the urban heat island effect. Meanwhile, the extent to which existing urban green infrastructure cools down an entire city’s surface temperatures (compared to the non-vegetated built-up areas) is referred to as cooling capacity. Hence, cooling capacity is a function of the total quantity of urban green infrastructure and its cooling efficiency (see Methods).
As a third step, we account for the spatial distributions of urban green infrastructure and populations to quantify the benefit of cooling mitigation received by an average urban inhabitant in each city given their location. This cooling benefit is a more direct measure of the cooling realized by people, after accounting for the within-city geography of urban green infrastructure and population density. We focus on cooling capacity and cooling benefit as the measures of the cooling capability of individual cities for assessing their global inequalities. We are particularly interested in linking cooling adaptation inequality with income inequality 40 , 46 . While this can be achieved using existing income metrics for country classifications 47 , here we use the traditional Global North/South classification due to its historical ties to geography which is influential in climate research.
Our analyses indicate that existing green infrastructure of an average city has a capability of cooling down surface temperatures by ~3 °C during warm seasons. However, a concerning disparity is evident; on average Global South cities have only two-thirds the cooling capacity and cooling benefit compared to Global North cities. This inequality is attributable to the differences in both quantity and quality of existing urban green infrastructure among cities. Importantly, we find that there exists considerable potential for many cities to enhance the cooling capability of their green infrastructure; achieving this potential could dramatically reduce global inequalities in adaptation to outdoor heat stress.
Our analyses showed that both the quantity and quality of the existing urban green infrastructure vary greatly among the world’s ~500 most populated cities (see Methods for details, and Fig. 1 for examples). The quantity of urban green infrastructure measured based on remotely sensed indicators of spectral greenness (Normalized Difference Vegetation Index, NDVI, see Methods) had a coefficient of variation (CV) of 35%. Similarly, the quality of urban green infrastructure in terms of cooling efficiency (daytime land surface temperatures during peak summer) had a CV of 37% (Supplementary Figs. 1 , 2 ). The global mean value of cooling capacity is 2.9 °C; existing urban green infrastructure ameliorates warm-season heat stress by 2.9 °C of surface temperature in an average city. In truth, however, the variation in cooling capacity was great (global CV in cooling capacity as large as ~50%), such that few cities were average. This variation is strongly geographically structured. Cities closer to the equator - tropical and subtropical cities - tend to have relatively weak cooling capacities (Fig. 2a, b ). As Global South countries are predominantly located at low latitudes, this pattern leads to a situation in which Global South cities, which tend to be hotter and relatively lower-income, have, on average, approximately two-thirds the cooling capacity of the Global North cities (2.5 ± 1.0 vs. 3.6 ± 1.7°C, Wilcoxon test, p = 2.7e-12; Fig. 2c ). The cities that most need to rely on green infrastructure are, at present, those that are least able to do so.
a , e , i , m , q Los Angeles, US. b , f , j , n , r Paris, France. c , g , k , o , s Shanghai, China. d , h , l , p , t Cairo, Egypt. Local cooling efficiency is calculated for different local climate zone types to account for within-city heterogeneity. In densely populated parts of cities, local cooling capacity tends to be lower due to reduced green space area, whereas local cooling benefit (local cooling capacity multiplied by a weight term of local population density relative to city mean) tends to be higher as more urban residents can receive cooling amelioration.
a Global distribution of cooling capacity for the 468 major urbanized areas. b Latitudinal pattern of cooling capacity. c Cooling capacity difference between the Global North and South cities. The cooling capacity offered by urban green infrastructure evinces a latitudinal pattern wherein lower-latitude cities have weaker cooling capacity ( b , cubic-spline fitting of cooling capacity with 95% confidence interval is shown), representing a significant inequality between Global North and South countries: city-level cooling capacity for Global North cities are about 1.5-fold higher than in Global South cities ( c ). Data are presented as box plots, where median values (center black lines), 25th percentiles (box lower bounds), 75th percentiles (box upper bounds), whiskers extending to 1.5-fold of the interquartile range (IQR), and outliers are shown. The tails of the cooling capacity distributions are truncated at zero as all cities have positive values of cooling capacity. Notice that no cities in the Global South have a cooling capacity greater than 5.5 °C ( c ). This is because no cities in the Global South have proportional green space areas as great as those seen in the Global North (see also Fig. 4b ). A similar pattern is found for cooling benefit (Supplementary Fig. 3 ). The two-sided non-parametric Wilcoxon test was used for statistical comparisons.
When we account for the locations of urban green infrastructure relative to humans within cities, the cooling benefit of urban green infrastructure realized by an average urban resident generally becomes slightly lower than suggested by cooling capacity (see Methods; Supplementary Fig. 3 ). Urban residents tend to be densest in the parts of cities with less green infrastructure. As a result, the average urban resident experiences less cooling amelioration than expected. However, this heterogeneity has only a minor effect on global-scale inequality. As a result, the geographic trends in cooling capacity and cooling benefit are similar: mean cooling benefit for an average urban resident also presents a 1.5-fold gap between Global South and North cities (2.2 ± 0.9 vs. 3.4 ± 1.7 °C, Wilcoxon test, p = 3.2e-13; Supplementary Fig. 3c ). Urban green infrastructure is a public good that has the potential to help even the most marginalized populations stay cool; unfortunately, this public benefit is least available in the Global South. When walking outdoors, the average person in an average Global South city receives only two-thirds the cooling amelioration from urban green infrastructure experienced by a person in an average Global North city. The high cooling amelioration capacity and benefit of the Global North cities is heavily influenced by North America (specifically, Canada and the US), which have both the highest cooling efficiency and the largest area of green infrastructure, followed by Europe (Supplementary Fig. 4 ).
One way to illustrate the global inequality of cooling capacity or benefit is to separately look at the cities that are most and least effective in ameliorating outdoor heat stress. Our results showed that ~85% of the 50 most effective cities (with highest cooling capacity or cooling benefit) are located in the Global North, while ~80% of the 50 least effective are Global South cities (Fig. 3 , Supplementary Fig. 5 ). This is true without taking into account the differences in the background temperatures and climate warming of these cities, which will exacerbate the effects on human health; cities in the Global South are likely to be closer to the limits of human thermal comfort and even, increasingly, the limits of the temperatures and humidities (wet-bulb temperatures) at which humans can safely work or even walk, such that the ineffectiveness of green spaces in those cities in cooling will lead to greater negative effects on human health 48 , work 14 , and gross domestic product (GDP) 49 . In addition, Global South cities commonly have higher population densities (Fig. 3 , Supplementary Fig. 5 ) and are projected to have faster population growth 50 . This situation will plausibly intensify the urban heat island effect because of the need of those populations for housing (and hence tensions between the need for buildings and the need for green spaces). It will also increase the number of people exposed to extreme urban heat island effects. Therefore, it is critical to increase cooling benefit via expanding urban green spaces, so that more people can receive the cooling mitigation from a given new neighboring green space if they live closer to each other. Doing so will require policies that incentivize urban green spaces as well as architectural innovations that make innovations such as plant-covered buildings easier and cheaper to implement.
The axes on the right are an order of magnitude greater than those on the left, such that the cooling capacity of Charlotte in the United States is about 37-fold greater than that of Mogadishu (Somalia) and 29-fold greater than that of Sana’a (Yemen). The cities presenting lowest cooling capacities are most associated with Global South cities at higher population densities.
Of course, cities differ even within the Global North or within the Global South. For example, some Global South cities have high green space areas (or relatively high cooling efficiency in combination with moderate green space areas) and hence high cooling capacity. These cities, such as Pune (India), will be important to study in more detail, to shed light on the mechanistic details of their cooling abilities as well as the sociopolitical and other factors that facilitated their high green area coverage and cooling capabilities (Supplementary Figs. 6 , 7 ).
We conducted our primary analyses using a spatial grain of 100-m grid cells and Landsat NDVI data for quantifying spectral greenness. Our results, however, were robust at the coarser spatial grain of 1 km. We find a slightly larger global cooling inequality (~2-fold gap between Global South and North cities) at the 1-km grain using MODIS data (see Methods and Supplementary Fig. 17 ). MODIS data have been frequently used for quantifying urban heat island effects and cooling mitigation 44 , 45 , 51 . Our results reinforce its robustness for comparing urban thermal environments between cities across broad scales.
The global inequality of cooling amelioration could have a number of proximate causes. To understand their relative influence, we first separately examined the effects of quality (cooling efficiency) and quantity (NDVI as a proxy indicator of urban green space area) of urban green infrastructure. The simplest null model is one in which cooling capacity (at the city scale) and cooling benefit (at the human scale) are driven primarily by the proportional area in a city dedicated to green spaces. Indeed, we found that both cooling capacity and cooling benefit were strongly correlated with urban green space area (Fig. 4 , Supplementary Fig. 8 ). This finding is useful with regards to practical interventions. In general, cities that invest in saving or restoring more green spaces will receive more cooling benefits from those green spaces. By contrast, differences among cities in cooling efficiency played a more minor role in determining the cooling capacity and benefit of cities (Fig. 4 , Supplementary Fig. 8 ).
a Relationship between cooling efficiency and cooling capacity. b Relationship between green space area (measured by mean Landsat NDVI in the hottest month of 2018) and cooling capacity. Note that the highest level of urban green space area in the Global South cities is much lower than that in the Global North (dashed line in b ). Gray bands indicate 95% confidence intervals. Two-sided t-tests were conducted. c A piecewise structural equation model based on assumed direct and indirect (through influencing cooling efficiency and urban green space area) effects of essential natural and socioeconomic factors on cooling capacity. Mean annual temperature and precipitation, and topographic variation (elevation range) are selected to represent basic background natural conditions; GDP per capita is selected to represent basic socioeconomic conditions. The spatial extent of built-up areas is included to correct for city size. A bi-directional relationship (correlation) is fitted between mean annual temperature and precipitation. Red and blue solid arrows indicate significantly negative and positive coefficients with p ≤ 0.05, respectively. Gray dashed arrows indicate p > 0.05. The arrow width illustrates the effect size. Similar relationships are found for cooling benefits realized by an average urban resident (see Supplementary Fig. 8 ).
A further question is what shapes the quality and quantity of urban green infrastructure (which in turn are driving cooling capacity)? Many inter-correlated factors are possibly operating at multiple scales, making it difficult to disentangle their effects, especially since experiment-based causal inference is usually not feasible for large-scale urban systems. From a macroscopic perspective, we test the simple hypothesis that the background natural and socioeconomic conditions of cities jointly affect their cooling capacity and benefit in both direct and indirect ways. To this end, we constructed a minimal structural equation model including only the most essential variables reflecting background climate (mean annual temperature and precipitation), topographic variation (elevation range), as well as gross domestic product (GDP) per capita and city area (see Methods; Fig. 4c ).
We found that the quantity of green spaces in a city (again, in proportion to its size) was positively correlated with GDP per capita and city area; wealthier cities have more green spaces. It is well known that wealth and green spaces are positively correlated within cities (the luxury effect) 40 , 46 ; our analysis shows that a similar luxury effect occurs among them at a global scale. In addition, larger cities often have proportionally more green spaces, an effect that may be due to the tendency for large cities (particularly in the US and Canada) to have lower population densities. Cities that were hotter and had more topographic variation tended to have fewer green spaces and those that were more humid tended to have more green spaces. Given that temperature and humidity are highly correlated with the geography of the Global South and Global North, it is difficult to know whether these effects are due to the direct effects of temperature and precipitation, for example, on the growth rate of vegetation and hence the transition of abandoned lots into green spaces, or are associated with historical, cultural and political differences that via various mechanisms correlate to climate. Our structural equation model explained only a small fraction of variation among cities in their cooling efficiency, which is to say the quality of their green space. Cooling efficiency was modestly influenced by background temperature and precipitation—the warmer a city, the greater the cooling efficiency in that city; conversely, the more humid a city the less the cooling efficiency of that city.
Our analyses suggested that the lower cooling adaptation capabilities of Global South cities can be explained by their lower quantity of green infrastructure and, to a much lesser extent, their weaker cooling efficiency (quality; Supplementary Fig. 2 ). These patterns appear to be in part structured by GDP, but are also associated with climatic conditions 39 , and other factors. A key question, unresolved by our work, is whether the climatic correlates of the size of green spaces in cities are due to the effects of climate per se or if they, instead, reflect correlates between contemporary climate and the social, cultural, and political histories of cities in the Global South 52 . Since urban planning has much inertia, especially in big cities, those choices might be correlated with climate because of the climatic correlates of political histories. It is also possible that these dynamics relate, in part, to the ways in which climate influences vegetation structure. However, this seems less likely given that under non-urban conditions vegetation cover (and hence cooling capacity) is normally positively correlated with mean annual temperature across the globe, opposite to our observed negative relationships for urban systems (Supplementary Fig. 9g ). Still, it is possible that increased temperatures in cities due to the urban heat island effects may lead to temperature-vegetation cover-cooling capacity relationships that differ from those in natural environments 53 , 54 . Indeed, a recent study found that climate warming will put urban forests at risk, and the risk is disproportionately higher in the Global South 55 .
Our model serves as a starting point for unraveling the mechanisms underlying global cooling inequality. We cannot rule out the possibility that other unconsidered factors correlated with the studied variables play important roles. We invite systematic studies incorporating detailed sociocultural and ecological variables to address this question across scales.
Can we reduce the inequality in cooling capacity and benefits that we have discovered among the world’s largest cities? Nuanced assessments of the potential to improve cooling mitigation require comprehensive considerations of socioeconomic, cultural, and technological aspects of urban management and policy. It is likely that cities differ greatly in their capacity to implement cooling through green infrastructure, whether as a function of culture, governance, policy or some mix thereof. However, any practical attempts to achieve greater cooling will occur in the context of the realities of climate and existing land use. To understand these realities, we modeled the maximum additional cooling capacity that is possible in cities, given existing constraints. We assume that this capacity depends on the quality (cooling efficiency) and quantity of urban green infrastructure. Our approach provides a straightforward metric of the cooling that could be achieved if all parts of a city’s green infrastructure were to be enhanced systematically.
The positive outlook is that our analyses suggest a considerable potential of improving cooling capacity by optimizing urban green infrastructure. An obvious way is through increases in urban green infrastructure quantity. We employ an approach in which we consider each local climate zone 56 to have a maximum NDVI and cooling efficiency (see Methods). For a given local climate zone, the city with the largest NDVI values or cooling efficiency sets the regional upper bounds for urban green infrastructure quantities or quality that can be achieved. Notably, these maxima are below the maxima for forests or other non-urban spaces for the simple reason that, as currently imagined, cities must contain gray (non-green) spaces in the form of roads and buildings. In this context, we conduct a thought experiment. What if we could systematically increase NDVI of all grid cells in each city, per local climate zone type, to a level corresponding to the median NDVI of grid cells in that upper bound city while keeping cooling efficiency unchanged (see Methods). If we were able to achieve this goal, the cooling capacity of cities would increase by ~2.4 °C worldwide. The increase would be even greater, ~3.8°C, if the 90th percentile (within the reference maximum city) was reached (Fig. 5a ). The potential for cooling benefit to the average urban resident is similar to that of cooling capacity (Supplementary Fig. 10a ). There is also potential to reduce urban temperatures if we can enhance cooling efficiency. However, the benefits of increases in cooling efficiency are modest (~1.5 °C increases at the 90th percentile of regional upper bounds) when holding urban green infrastructure quantity constant. In theory, if we could maximize both quantity and cooling efficiency of urban green infrastructure (to 90th percentiles of their regional upper bounds respectively), we would yield increases in cooling capacity and benefit up to ~10 °C, much higher than enhancing green space area or cooling efficiency alone (Fig. 5a , Supplementary Fig. 10a ). Notably, such co-maximization of green space area and cooling efficiency would substantially reduce global inequality to Gini <0.1 (Fig. 5b , Supplementary Fig. 10b ). Our analyses thus provide an important suggestion that enhancing both green space quantity and quality can yield a synergistic effect leading to much larger gains than any single aspect alone.
a The potential of enhancing cooling capacity via either enhancing urban green infrastructure quality (i.e., cooling efficiency) while holding quantity (i.e., green space area) fixed (yellow), or enhancing quantity while holding quality fixed (blue) is much lower than that of enhancing both quantity and quality (green). The x-axis indicates the targets of enhancing urban green infrastructure quantity and/or quality relative to the 50–90th percentiles of NDVI or cooling efficiency, see Methods). The dashed horizontal lines indicate the median cooling capacity of current cities. Data are presented as median values with the colored bands corresponding to 25–75th percentiles. b The potential of reducing cooling capacity inequality is also higher when enhancing both urban green infrastructure quantity and quality. The Gini index weighted by population density is used to measure inequality. Similar results were found for cooling benefit (Supplementary Fig. 10 ).
Different estimates of cooling capacity potential may be reached based on varying estimates and assumptions regarding the maximum possible quantity and quality of urban green infrastructure. There is no single, simple way to make these estimates, especially considering the huge between-city differences in society, culture, and structure across the globe. Our example case (above) begins from the upper bound city’s median NDVI, taking into account different local climate zone types and background climate regions (regional upper bounds). This is based on the assumption that for cities within the same climate regions, their average green space quantity may serve as an attainable target. Still, urban planning is often made at the level of individual cities, often only implemented to a limited extent and made with limited consideration of cities in other regions and countries. A potentially more realistic reference may be taken from the existing green infrastructure (again, per local climate zone type) within each particular city itself (see Methods): if a city’s sparsely vegetated areas was systematically elevated to the levels of 50–90th percentiles of NDVI within their corresponding local climate zones within the city, cooling capacity would still increase, but only by 0.5–1.5 °C and with only slightly reduced inequalities among cities (Supplementary Fig. 11 ). This highlights that ambitious policies, inspired by the greener cities worldwide, are necessary to realize the large cooling potential in urban green infrastructure.
In summary, our results demonstrate clear inequality in the extent to which urban green infrastructure cools cities and their denizens between the Global North and South. Much attention has been paid to the global inequality of indoor heat adaptation arising from the inequality of resources (e.g., less affordable air conditioning and more frequent power shortages in the Global South) 36 , 57 , 58 , 59 . Our results suggest that the inequality in outdoor adaptation is particularly concerning, especially as urban populations in the Global South are growing rapidly and are likely to face the most severe future temperature extremes 60 .
Previous studies have been focusing on characterizing urban heat island effects, urban vegetation patterns, resident exposure, and cooling effects in particular cities 26 , 28 , 34 , 61 , regions 22 , 25 , 62 , or continents 32 , 44 , 63 . Recent studies start looking at global patterns with respect to cooling efficiency or green space exposure 35 , 45 , 64 , 65 . Our approach is one drawn from the fields of large-scale ecology and macroecology. This approach is complementary to and, indeed, can, in the future, be combined with (1) mechanism driven biophysical models 66 , 67 to predict the influence of the composition and climate of green spaces on their cooling efficiency, (2) social theory aimed at understanding the factors that govern the amount of green space in cities as well as the disparity among cities 68 , (3) economic models of the effects of policy changes on the amount of greenspace and even (4) artist-driven projects that seek to understand the ways in which we might reimagine future cities 69 . Our simple explanatory model is, ultimately, one lens on a complex, global phenomenon.
Our results convey some positive outlook in that there is considerable potential to strengthen the cooling capability of cities and to reduce inequalities in cooling capacities at the same time. Realizing this nature-based solution, however, will be challenging. First, enhancing urban green infrastructure requires massive investments, which are more difficult to achieve in Global South cities. Second, it also requires smart planning strategies and advanced urban design and greening technologies 37 , 70 , 71 , 72 . Spatial planning of urban green spaces needs to consider not only the cooling amelioration effect, but also their multifunctional aspects that involve multiple ecosystem services, mental health benefits, accessibility, and security 73 . In theory, a city can maximize its cooling while also maximizing density through the combination of high-density living, ground-level green spaces, and vertical and rooftop gardens (or even forests). In practice, the current cities with the most green spaces tend to be lower-density cities 74 (Supplementary Fig. 12 ). Still, innovation and implementation of new technologies that allow green spaces and high-density living to be combined have the potential to reduce or disconnect the negative relationship between green space area and population density 71 , 75 . However, this development has yet to be realized. Another dimension of green spaces that deserves more attention is the geography of green spaces relative to where people are concentrated within cities. A critical question is how best should we distribute green spaces within cities to maximize cooling efficiency 76 and minimize within-city cooling inequality towards social equity 77 ? Last but not least, it is crucial to design and manage urban green spaces to be as resilient as possible to future climate stress 78 . For many cities, green infrastructure is likely to remain the primary means people will have to rely on to mitigate the escalating urban outdoor heat stress in the coming decades 79 .
We used the world population data from the World’s Cities in 2018 Data Booklet 80 to select 502 major cities with population over 1 million people (see Supplementary Data 1 for the complete list of the studied cities). Cities are divided into the Global North and Global South based on the Human Development Index (HDI) from the Human Development Report 2019 81 . For each selected city, we used the 2018 Global Artificial Impervious Area (GAIA) data at 30 m resolution 82 to determine its geographic extent. The derived urban boundary polygons thus encompass a majority of the built-up areas and urban residents. In using this approach, rather than urban administrative boundaries, we can focus on the relatively densely populated areas where cooling mitigation is most needed, and exclude areas dominated by (semi) natural landscapes that may bias the subsequent quantifications of the cooling effect. Our analyses on the cooling effect were conducted at the 100 m spatial resolution using Landsat data and WorldPop Global Project Population Data of 2018 83 . In order to test for the robustness of the results to coarser spatial scales, we also repeated the analyses at 1 km resolution using MODIS data, which have been extensively used for quantifying urban heat island effects and cooling mitigation 44 , 45 , 51 . We discarded the five cities with sizes <30 km 2 as they were too small for us to estimate their cooling efficiency based on linear regression (see section below for details). We combined closely located cities that form contiguous urban areas or urban agglomerations, if their urban boundary polygons from GAIA merged (e.g., Phoenix and Mesa in the United States were combined). Our approach yielded 468 polygons, each representing a major urbanized area that were the basis for all subsequent analyses. Because large water bodies can exert substantial and confounding cooling effects, we excluded permanent water bodies including lakes, reservoirs, rivers, and oceans using the Copernicus Global Land Service (CGLS) Land Cover data for 2018 at 10 m resolution 84 .
As a first step, we calculated cooling efficiency for each studied city within the GAIA-derived urban boundary. Cooling efficiency quantifies the extent to which a given area of green spaces in a city can reduce temperatures. It is a measure of the effectiveness (quality) of urban green spaces in terms of heat amelioration. Cooling efficiency is typically measured by calculating the slope of the relationship between remotely-sensed land surface temperature (LST) and vegetation cover through ordinary least square regression 42 , 44 , 45 . It is known that cooling efficiency varies between cities. Influencing factors might include background climate 29 , species composition 30 , 85 , landscape configuration 28 , topography 86 , proximity to large water bodies 33 , 87 , urban morphology 88 , and city management practices 31 . However, the mechanism underlying the global pattern of cooling efficiency remains unclear.
We used Landsat satellite data provided by the United States Geological Survey (USGS) to calculate the cooling efficiency of each studied city. We used the cloud-free Landsat 8 Level 2 LST and NDVI data. For each city we calculated the mean LST in each month of 2018 to identify the hottest month, and then derived the hottest month LST; we used the cloud-free Landsat 8 data to calculate the mean NDVI for the hottest month correspondingly.
We quantified cooling efficiency for different local climate zones 56 separately for each city, to account for within-city variability of thermal environments. To this end, we used the Copernicus Global Land Service data (CGLS) 84 and Global Human Settlement Layers (GHSL) Built-up height data 89 of 2018 at the 100 m resolution to identify five types of local climate zones: non-tree vegetation (shrubs, herbaceous vegetation, and cultivated vegetation according to the CGLS classification system), low-rise buildings (built up and bare according to the CGLS classification system, with building heights ≤10 m according to the GHSL data), medium-high-rise buildings (built up and bare areas with building heights >10 m), open tree cover (open forest with tree cover 15–70% according to the CGLS system), and closed tree cover (closed forest with tree cover >70%).
For each local climate zone type in each city, we constructed a regression model with NDVI as the predictor variable and LST as the response variable (using the ordinary least square method). We took into account the potential confounding factors including topographic elevation (derived from MERIT DEM dataset 90 ), building height (derived from the GHSL dataset 89 ), and distance to water bodies (derived from the GSHHG dataset 91 ), the model thus became: LST ~ NDVI + topography + building height + distance to water. Cooling efficiency was calculated as the absolute value of the regression coefficient of NDVI, after correcting for those confounding factors. To account for the multi-collinearity issue, we conducted variable selection based on the variance inflation factor (VIF) to achieve VIF < 5. Before the analysis, we discarded low-quality Landsat pixels, and filtered out the pixels with NDVI < 0 (normally less than 1% in a single city). Cooling efficiency is known to be influenced by within-city heterogeneity 92 , 93 , and, as a result, might sometimes better fit non-linear relationships at local scales 65 , 76 . However, our central aim is to assess global cooling inequality based on generalized relationships that fit the majority of global cities. Previous studies have shown that linear relationships can do this job 42 , 44 , 45 , therefore, here we used linear models to assess cooling efficiency.
As a second step, we calculated the cooling capacity of each city. Cooling capacity is a positive function of the magnitude of cooling efficiency and the proportional area of green spaces in a city and is calculated based on NDVI and the derived cooling efficiency (Eq. 1 , Supplementary Fig. 13 ):
where CC lcz and CE lcz are the cooling capacity and cooling efficiency for a given local climate zone type in a city, respectively; NDVI i is the mean NDVI for 100-m grid cell i ; NDVI min is the minimum NDVI across the city; and n is the total number of grid cells within the local climate zone. Local cooling capacity for each grid cell i (Fig. 1 , Supplementary Fig. 7 ) can be derived in this way as well (Supplementary Fig. 13 ). For a particular city, cooling capacity may be dependent on the spatial configuration of its land use/cover 28 , 94 , but here we condensed cooling capacity to city average (Eq. 2 ), thus did not take into account these local-scale factors.
where CC is the average cooling capacity of a city; n lcz is the number of grid cells of the local climate zone; m is the total number of grid cells within the whole city.
As a third step, we calculated the cooling benefit realized by an average urban resident (cooling benefit in short) in each city. Cooling benefit depends not only on the cooling capacity of a city, but also on where people live within a city relative to greener or grayer areas of the city. For example, cooling benefits in a city might be low even if the cooling capacity is high if the green parts and the dense-population parts of a city are inversely correlated. Here, we are calculating these averages while aware that in any particular city the exposure of a particular person will depend on the distribution of green spaces in a city, and the occupation, movement trajectories of a person, etc. On the scale of a city, we calculated cooling benefit following a previous study 35 , that is, simply adding a weight term of population size per 100-m grid cell into cooling capacity in Eq. ( 1 ):
Where CB lcz is the cooling benefit of a given local climate zone type in a specific city, pop i is the number of people within grid cell i , \(\overline{{pop}}\) is the mean population of the city.
Where CB is the average cooling benefit of a city. The population data were obtained from the 100-m resolution WorldPop Global Project Population Data of 2018 83 . Local cooling benefit for a given grid cell i can be calculated in a similar way, i.e., local cooling capacity multiplied by a weight term of local population density relative to mean population density. Local cooling benefits were mapped for example cities for the purpose of illustrating the effect of population spatial distribution (Fig. 1 , Supplementary Fig. 7 ), but their patterns were not examined here.
Based on the aforementioned three key variables quantified at 100 m grid cells, we conducted multivariate analyses to examine if and to what extent cooling efficiency and cooling benefit are shaped by essential natural and socioeconomic factors, including background climate (mean annual temperature from ECMWF ERA5 dataset 95 and precipitation from TerraClimate dataset 96 ), topography (elevation range 90 ), and GDP per capita 97 , with city size (geographic extent) corrected for. We did not include humidity because it is strongly correlated with temperature and precipitation, causing serious multi-collinearity problems. We used piecewise structural equation modeling to test the direct effects of these factors and indirect effects via influencing cooling efficiency and vegetation cover (Fig. 4c , Supplementary Fig. 8c ). To account for the potential influence of spatial autocorrelation, we used spatially autoregressive models (SAR) to test for the robustness of the observed effects of natural and socioeconomic factors on cooling capacity and benefit (Supplementary Fig. 14 ).
We conducted the following additional analyses to test for robustness. We obtained consistent results from these robustness analyses.
(1) We looked at the mean hottest-month LST and NDVI within 3 years (2017-2019) to check the consistency between the results based on relatively short (1 year) vs. long (3-year average) time periods (Supplementary Fig. 15 ).
(2) We carried out the approach at a coarser spatial scale of 1 km, using MODIS-derived NDVI and LST, as well as the population data 83 in the hottest month of 2018. In line with our finer-scale analysis of Landsat data, we selected the hottest month and excluded low-quality grids affected by cloud cover and water bodies 98 (water cover > 20% in 1 × 1 km 2 grid cells) of MODIS LST, and calculated the mean NDVI for the hottest month. We ultimately obtained 441 cities (or urban agglomerations) for analysis. At the 1 km resolution, some local climate zone types would yield insufficient samples for constructing cooling efficiency models. Therefore, instead of identifying local climate zone explicitly, we took an indirect approach to account for local climate confounding factors, that is, we constructed a multiple regression model for a whole city incorporating the hottest-month local temperature 95 , precipitation 96 , and humidity (based on NASA FLDAS dataset 99 ), albedo (derived from the MODIS MCD43A3 product 100 ), aerosol loading (derived from the MODIS MCD19A2 product 101 ), wind speed (based on TerraClimate dataset 96 ), topography elevation 90 , distance to water 91 , urban morphology (building height 102 ), and human activity intensity (VIIRS nighttime light data as a proxy indicator 103 ). We used the absolute value of the linear regression coefficient of NDVI as the cooling efficiency of the whole city (model: LST ~ NDVI + temperature + precipitation + humidity + distance to water + topography + building height + albedo + aerosol + wind speed + nighttime light), and calculated cooling capacity and cooling benefit based on the same method. Variable selection was conducted using the criterion of VIF < 5.
Our results indicated that MODIS-based cooling capacity and cooling benefit are significantly correlated with the Landsat-based counterparts (Supplementary Fig. 16 ); importantly, the gap between the Global South and North cities is around two-fold, close to the result from the Landsat-based result (Supplementary Fig. 17 ).
(3) For the calculation of cooling benefit, we considered different spatial scales of human accessibility to green spaces: assuming the population in each 100 × 100 m 2 grid cell could access to green spaces within neighborhoods of certain extents, we calculated cooling benefit by replacing NDVI i in Eq. ( 3 ) with mean NDVI within the 300 × 300 m 2 and 500 × 500 m 2 extents centered at the focal grid cell (Supplementary Fig. 18 ).
(4) Considering cities may vary in minimum NDVI, we assessed if this variation could affect resulting cooling capacity patterns. To this end, we calculated the cooling capacity for each studied city using NDVI = 0 as the reference (i.e., using NDVI = 0 instead of minimum NDVI in Supplementary Fig. 13b ), and correlated it with that using minimum NDVI as the reference (Supplementary Fig. 19 ).
Inequalities in access to the benefits of green spaces in cities exist within cities, as is increasingly well-documented 104 . Here, we focus instead on the inequalities among cities. We used the Gini coefficient to measure the inequality in cooling capacity and cooling benefit between all studied cities across the globe as well as between Global North or South cities. We calculated Gini using the population-density weighted method (Fig. 5b ), as well as the unweighted and population-size weighted methods (Supplementary Fig. 20 ).
We estimated the potential of enhancing cooling amelioration based on the assumptions that urban green space quality (cooling efficiency) and quantity (NDVI) can be increased to different levels, and that relative spatial distributions of green spaces and population can be idealized (so that their spatial matches can maximize cooling benefit). We assumed that macro-climate conditions act as the constraints of vegetation cover and cooling efficiency. We calculated the 50th, 60th, 70th, 80th, and 90th percentiles of NDVI within each type of local climate zone of each city. For a given local climate zone type, we obtained the city with the highest NDVI per percentile value as the regional upper bounds of urban green infrastructure quantity. The regional upper bounds of cooling efficiency are derived in a similar way. For each local climate zone in a city, we generated a potential NDVI distribution where all grid cells reach the regional upper bound values for the 50th, 60th, 70th, 80th, or 90th percentile of urban green space quantity or quality, respectively. NDVI values below these percentiles were increased, whereas those above these percentiles remained unchanged. The potential estimates are essentially dependent on the references, i.e., the optimal cooling efficiency and NDVI that a given city can reach. However, such references are obviously difficult to determine, because complex natural and socioeconomic conditions could play important roles in determining those cooling optima, and the dominant factors are unknown at a global scale. We employed the simplifying assumption that background climate could act as an essential constraint according to our results. We therefore used the Köppen climate classification system 105 to determine the reference separately in each climate region (tropical, arid, temperate, and continental climate regions were involved for all studied cities).
We calculated potential cooling capacity and cooling benefit based on these potential NDVI maps (Fixed cooling efficiency in Fig. 5 ). We then calculated the potentials if cooling efficiency of each city can be enhanced to 50–90th percentile across all urban local climate zones within the corresponding biogeographic region (Fixed green space area in Fig. 5 ). We also calculated the potentials if both NDVI and cooling efficiency were enhanced (Enhancing both in Fig. 5) to a certain corresponding level (i.e., i th percentile NDVI + i th percentile cooling efficiency). We examined if there are additional effects of idealizing relative spatial distributions of urban green spaces and humans on cooling benefits. To this end, the pixel values of NDVI or population amount remained unchanged, but their one-to-one correspondences were based on their ranking: the largest population corresponds to the highest NDVI, and so forth. Under each scenario, we calculated cooling capacity and cooling benefit for each city, and the between-city inequality was measured by the Gini coefficient.
We used the Google Earth Engine to process the spatial data. The statistical analyses were conducted using R v4.3.3 106 , with car v3.1-2 107 , piecewiseSEM v2.1.2 108 , and ineq v0.2-13 109 packages. The global maps of cooling were created using the ArcGIS v10.3 software.
Further information on research design is available in the Nature Portfolio Reporting Summary linked to this article.
City population statistics data is collected from the Population Division of the Department of Economic and Social Affairs of the United Nations ( https://www.un.org/development/desa/pd/content/worlds-cities-2018-data-booklet ). Global North-South division is based on Human Development Report 2019 which from United Nations Development Programme ( https://hdr.undp.org/content/human-development-report-2019 ). Global urban boundaries from GAIA data are available from Star Cloud Data Service Platform ( https://data-starcloud.pcl.ac.cn/resource/14 ) . Global water data is derived from 2018 Copernicus Global Land Service (CGLS 100-m) data ( https://developers.google.com/earth-engine/datasets/catalog/COPERNICUS_Landcover_100m_Proba-V-C3_Global ), European Space Agency (ESA) WorldCover 10 m 2020 product ( https://developers.google.com/earth-engine/datasets/catalog/ESA_WorldCover_v100 ), and GSHHG (A Global Self-consistent, Hierarchical, High-resolution Geography Database) at https://www.soest.hawaii.edu/pwessel/gshhg/ . Landsat 8 LST and NDVI data with 30 m resolution are available at https://developers.google.com/earth-engine/datasets/catalog/LANDSAT_LC08_C02_T1_L2 . Land surface temperature (LST) data with 1 km from MODIS Aqua product (MYD11A1) is available at https://developers.google.com/earth-engine/datasets/catalog/MODIS_061_MYD11A1 . NDVI (1 km) dataset from MYD13A2 is available at https://developers.google.com/earth-engine/datasets/catalog/MODIS_061_MYD13A2 . Population data (100 m) is derived from WorldPop ( https://developers.google.com/earth-engine/datasets/catalog/WorldPop_GP_100m_pop ). Local climate zones are also based on 2018 CGLS data ( https://developers.google.com/earth-engine/datasets/catalog/COPERNICUS_Landcover_100m_Proba-V-C3_Global ), and built-up height data is available from Global Human Settlement Layers (GHSL, 100 m) ( https://developers.google.com/earth-engine/datasets/catalog/JRC_GHSL_P2023A_GHS_BUILT_H ). Temperature data is calculated from ERA5-Land Monthly Aggregated dataset ( https://developers.google.com/earth-engine/datasets/catalog/ECMWF_ERA5_LAND_MONTHLY_AGGR ). Precipitation and wind data are calculated from TerraClimate (Monthly Climate and Climatic Water Balance for Global Terrestrial Surfaces, University of Idaho) ( https://developers.google.com/earth-engine/datasets/catalog/IDAHO_EPSCOR_TERRACLIMATE ). Humidity data is calculated from Famine Early Warning Systems Network (FEWS NET) Land Data Assimilation System ( https://developers.google.com/earth-engine/datasets/catalog/NASA_FLDAS_NOAH01_C_GL_M_V001 ). Topography data from MERIT DEM (Multi-Error-Removed Improved-Terrain DEM) product is available at https://developers.google.com/earth-engine/datasets/catalog/MERIT_DEM_v1_0_3 . GDP from Gross Domestic Product and Human Development Index dataset is available at https://doi.org/10.5061/dryad.dk1j0 . VIIRS nighttime light data is available at https://developers.google.com/earth-engine/datasets/catalog/NOAA_VIIRS_DNB_MONTHLY_V1_VCMSLCFG . City building volume data from Global 3D Building Structure (1 km) is available at https://doi.org/10.34894/4QAGYL . Albedo data is derived from the MODIS MCD43A3 product ( https://developers.google.com/earth-engine/datasets/catalog/MODIS_061_MCD43A3 ), and aerosol data is derived from the MODIS MCD19A2 product ( https://developers.google.com/earth-engine/datasets/catalog/MODIS_061_MCD19A2_GRANULES ). All data used for generating the results are publicly available at https://doi.org/10.6084/m9.figshare.26340592.v1 .
The codes used for data collection and analyses are publicly available at https://doi.org/10.6084/m9.figshare.26340592.v1 .
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We thank all the data providers. We thank Marten Scheffer for valuable discussion. C.X. is supported by the National Natural Science Foundation of China (Grant No. 32061143014). J.-C.S. was supported by Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), funded by Danish National Research Foundation (grant DNRF173), and his VILLUM Investigator project “Biodiversity Dynamics in a Changing World”, funded by VILLUM FONDEN (grant 16549). W.Z. was supported by the National Science Foundation of China through Grant No. 42225104. T.M.L. and J.F.A. are supported by the Open Society Foundations (OR2021-82956). W.J.R. is supported by the funding received from Roger Worthington.
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School of Life Sciences, Nanjing University, Nanjing, China
Yuxiang Li, Shuqing N. Teng & Chi Xu
Center for Ecological Dynamics in a Novel Biosphere (ECONOVO), Department of Biology, Aarhus University, Aarhus, Denmark
Jens-Christian Svenning
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
University of Chinese Academy of Sciences, Beijing, China
Beijing Urban Ecosystem Research Station, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
School for Environment and Sustainability, University of Michigan, Ann Arbor, MI, USA
Global Systems Institute, University of Exeter, Exeter, UK
Jesse F. Abrams & Timothy M. Lenton
Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR, USA
William J. Ripple
Department of Environmental Science and Engineering, Fudan University, Shanghai, China
Department of Applied Ecology, North Carolina State University, Raleigh, NC, USA
Robert R. Dunn
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Y.L., S.N.T., R.R.D., and C.X. designed the study. Y.L. collected the data, generated the code, performed the analyses, and produced the figures with inputs from J.-C.S., W.Z., K.Z., J.F.A., T.M.L., W.J.R., Z.Y., S.N.T., R.R.D. and C.X. Y.L., S.N.T., R.R.D. and C.X. wrote the first draft with inputs from J.-C.S., W.Z., K.Z., J.F.A., T.M.L., W.J.R., and Z.Y. All coauthors interpreted the results and revised the manuscript.
Correspondence to Shuqing N. Teng , Robert R. Dunn or Chi Xu .
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The authors declare no competing interests.
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Li, Y., Svenning, JC., Zhou, W. et al. Green spaces provide substantial but unequal urban cooling globally. Nat Commun 15 , 7108 (2024). https://doi.org/10.1038/s41467-024-51355-0
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Change is a common experience in complex health care systems. Staff, patients and visitors come and go []; leadership, models of care, workforce and governing structures are reshaped in response to policy and legislative change [], and new technologies and equipment are introduced or retired [].In addition to these common changes experienced throughout health care, the acute sector in many ...
In our book 'Health Systems Improvement Across the Globe: Success Stories from 60 Countries', we gathered case-study accomplishments from 60 countries. A unique feature of the collection is the diversity of included countries, from the wealthiest and most politically stable such as Japan, Qatar and Canada, to some of the poorest, most ...
Health systems also need a larger workforce, but although the global economy could create 40 million new health-sector jobs by 2030, there is still a projected shortfall of 9.9 million physicians, ... this report looked at 23 applications in use today and provides case studies of 14 applications already in use. These illustrate the full range ...
1. Introduction. Artificial intelligence (AI) is defined as the intelligence of machines, as opposed to the intelligence of humans or other living species [1], [2].AI can also be defined as the study of "intelligent agents"—that is, any agent or device that can perceive and understand its surroundings and accordingly take appropriate action to maximize its chances of achieving its ...
July 25, 2024 - Surveyed healthcare leaders say their organizations are eager to use generative AI to help enhance how healthcare stakeholders work and operate, ... December 19, 2023 - The healthcare services sector has seen rapid growth over recent years. Despite the challenges organizations may face in 2024,...
2024 Global Health Care Sector Outlook. 6 MB PDF. Lingering COVID-19 effects are still contributing to widespread labor shortages and escalating costs, while the adoption of artificial intelligence (AI) presents possible solutions. Predicted to play a pivotal role in streamlining health care processes, AI promises precision and efficiency from ...
Healthcare providers can allocate resources more efficiently, prioritize high-risk patients, and deliver targeted interventions, ultimately improving patient satisfaction and healthcare quality. Related: Role of CDO in the Healthcare Sector . Case Study 6: AI in Epidemic Outbreak Prediction Background
innovation in healthcare: A case study of hospitals as innovation platforms ' presented. at MakeLearn and TIIM International Conference, Piran, Slovenia, 15- 17 May 2019. 1 Introduction. Cost ...
A case study approach [ 47, 48] was adopted here to understand the deployment of a whole system change in the acute hospital along the four dimensions of STS outlined above. A case study is an approach that is used to generate an in-depth, multi-faceted understanding of a complex issue in its real-life context [ 49 ].
Ya-Ting Yang, Yi-Hsin Elsa Hsu, Kung-Pei Tang, Christine Wang, Stephen Timmon, Wen-Ta Chiu, Saileela Annavajjula, Jan-Show Chu, Case study: international healthcare service quality, building a model for cultivating cultural sensitivity, International Journal for Quality in Health Care, Volume 32, Issue 9, November 2020, Pages 639-642, https ...
The healthcare sector offers a compelling mix of defensive characteristics and growth potential driven by innovation. It also features ample dispersion that presents stock pickers with an opportunity to parse potential leaders and laggards in pursuit of above-market return. ... The above case study is just one example of how active stock ...
Each case study takes a single telemedicine project or service as a unit of analysis. 3.2. The selected case studies. When selecting the case studies, it was important that the "appropriateness and the adequacy" (Shakir, 2002) to the research was maintained. In other words, we needed to ensure that the criteria were met to ensure the ...
A healthcare firm's journey towards achieving 96% precision in monthly claims reserve forecasts. Elevating care management for a health plan covering 4.7 million members. Tackling data security and access challenges for a multi-state health insurer. Achieving Lightning-Fast Case Resolution In Under A Minute For A Leading Managed Care Company.
'Big data' is massive amounts of information that can work wonders. It has become a topic of special interest for the past two decades because of a great potential that is hidden in it. Various public and private sector industries generate, store, and analyze big data with an aim to improve the services they provide. In the healthcare industry, various sources for big data include hospital ...
The first wave. In India, the first case of COVID-19 infection was reported on 27TH January 2020, when a 20 year old female with a travel history of China presented with a sore throat and dry cough in the emergency department of General Hospital, Thrissur, Kerala. 4 Since then, COVID-19 has taken a serious toll in India and worldwide. To prevent the spread of COVID-19 infection, the Government ...
The 4 case studies by Penn Nursing illustrate how nurses can be really powerful collaborators and generators of solutions within Healthcare. The videos describe the main attributes that nurses bring to the problem solving table. Empathy. A big part of a nurses role is to be able to empathize with their patients, so it comes naturally to nurses.
The validity of the results can be improved by including more hospitals and more case studies from the healthcare sector in different countries.,The findings will enable researchers, academicians and practitioners to incorporate the results of the study in LSS implementation within the healthcare system to increase the likelihood of successful ...
This case study demonstrates the power of a commitment to CQI as a driver for excellence in healthcare. The healthcare industry is rich with case studies that provide valuable insights and lessons learned. By analyzing and understanding these success stories, healthcare providers can apply similar strategies to achieve positive outcomes in ...
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When conducting QLR, time is the lens used to inform the overall study design and processes of data collection and analysis. While QLR is an evolving methodology, spanning diverse disciplines (Holland et al., 2006), a key feature is the collection of data on more than one occasion, often described as waves (Neale, 2021).Thus, researchers embarking on designing a new study need to consider ...
Background Kenya grapples with a paradox; severe public sector workforce shortages co-exist with rising unemployment among healthcare professionals. Medical schools have increased trainee outputs, but only 45% of newly qualified/registered doctors were absorbed by the public sector during 2015-2018. In such a context, we explore what influences doctors' career choices at labour market ...
Case study - Ahmed Making a difference to people's health and wellbing Find out about Ahmed Abukar's role as a Brent Health Matters Community Champion. Ahmed joined BHM as a volunteer Community Champion in May 2022, before being employed as a Community Coordinator in September 2023. ... Ahmed works in the Harlesden area, where he applies his ...
The South-East Asia Region Primary Health Care Strategy 2022-2030 outlines key actions to transform health systems through a primary health care approach. ... the private sector, and civil society to achieve universal health coverage. According to the Lancet Commission, nearly 60% of the 8.6 million annual deaths from treatable conditions are ...
The study uses the concept of habitus to understand whether the changing design of traditional rondavels has influenced their utilisation, based on a case study of the Mbhashe Local Municipality ...
Even before such lethal temperatures are reached, worker productivity 13 and general health and well-being 14 can suffer. ... a case study in Lagos, Nigeria. Sci. Rep. 12, 14168 (2022).