Two-step Floating Catchment Area Method Research Articles

Spatial Difference and Equity Analysis for Accessibility to Three-Level Medical Services Based on Actual Medical Behavior in Shaanxi, China.

The contradiction between the supply and demand of public medical resources in China is serious. On the basis of the “graded diagnosis and treatment” model, the Chinese government divides the medical grade and adjusts the allocation of medical facilities so as to alleviate the adverse impact of these issues on residents’ health. Although the government tries to guide residents’ medical treatment according to the level of medical facilities, there are differences between residents’ medical treatment mode and policy rules in reality. Therefore, it is of great significance to explore spatial differences in accessibility to medical services for residents on the basis of the actual medical behavior. This article takes Shaanxi province as the research area, and uses the improved node cost network analysis method with the space-time distance model and the two-step floating catchment area method, respectively, to analyze the spatial differences of accessibility to three-level medical services and evaluate the equity of accessibility in different areas and groups in Shaanxi. Results showed that the overall level of accessibility to primary medical services in the province is good, and spatial distribution is balanced; the polarization of accessibility to secondary and tertiary medical services is a serious issue, and within the research area, a band-shaped multicore spatial structure was formed with the built-up areas of various cities as high-level centers of accessibility. Provincial residents have poor equity to access three-level medical services, and the equity of accessibility to primary medical services is better than that to highly specialized medical services. There is no obvious gap between accessibility to three-level medical services for the aging and the nonaging populations in Shaanxi, but the unfair phenomenon between agricultural and the nonagricultural populations is prominent. In addition, this article found that the improvement in traffic conditions can produce space-time convergence and effectively weaken spatial deprivation. Therefore, developing public transportation is an effective approach to improve the equity of accessibility to medical services.

Measuring potential assisted-transport demand for older adult care-recipients in Hamilton, Canada

IntroductionCarer-employees are defined as individuals who are providing unpaid care usually to a loved one or friend while simultaneously working in the paid labour force. This specific population group is vulnerable to ill-health due to the various challenges faced in managing work-life balance. One of the most demanding and common caregiving tasks in Canada is assisted-transport, which involves running errands for the care-recipient, or driving the care recipient to appointments. Little is known about assisted-transport, except that the frequency of assisted-transport is based on the links between daily constraints and carer-employees’ care tasks; thereby, directly impacting work-life balance. An alternative to mitigate assisted-transport demand is to improve the independent mobility of care-recipients (older adults) using accessibility to services as a demand measurement index. Therefore, this research explores potential accessibility to vital services for the older adult, suggesting areas that may require service intervention within the Hamilton census metropolitan area (CMA) in Ontario, Canada. MethodsThe Enhanced Two-Step Floating Catchment Area method was used to analyze potential accessibility from residential addresses of those aged 65+ to vital services; access zones were then outlined. Older adult populations for each access zone were calculated using census data. Suggested areas for service implementation were identified using quadrat analyses of addresses via hexabins. ResultsResults inform the location of care-recipients living in potentially underserved areas (high assisted-transport demand) of the Hamilton CMA and, in so doing, provide visual insight for decision-makers and city planners to better mitigate mobility dependence.

The capitalization of spatial healthcare accessibility into house prices in Taiwan: an application of spatial quantile regression

Purpose Population ageing is fast becoming a major social concern across the globe. This ageing trend unavoidably fuels elders’ demand for healthcare services. As the main users of health care service, whether the healthcare is geographically approachable in local areas is more imperative to senior residents with restricted mobility. This paper proposes to examine the effect of elders’ healthcare accessibility on property prices of Taipei Metropolis, Taiwan. Design/methodology/approach Luo and Qi’s (2009) enhanced two-step floating catchment area method – taking both healthcare demand and supply into account – was used to measure three types of healthcare services: “physician-to-elder ratio”, “hospital bed-to-elder ratio” and “ambulance-to-elder ratio”. Spatial quantile regression (SQR) model was then used to examine the spatial effect of healthcare accessibility on different property price ranges. Findings The “physician-to-elder ratio” and “hospital bed-to-elder ratio” demonstrated expected consistent positive effects across all quantiles of property prices (p < 0.01) in SQR, and its effects aggravated as the quantiles of property prices rose. The “ambulance-to-elder ratio” demonstrated a non-linear influence on property prices (i.e. a negative effect on lowest quantile prices but a positive on higher quantile prices) possibly due to the semi-obnoxious characteristic of the ambulance. That is, residents living in lower priced neighbourhoods may dislike ambulances’ annoying sound of sirens (i.e. ambulances’ disamenity), while residents living in higher valued neighbourhoods may on the contrary appreciate ambulances’ healthcare services (i.e. amenity). Practical implications These findings are expected to offer some insights for government’s policies in providing elders in their later years with good residential quality and easy access to healthcare resource. Originality/value This paper is one of the few studies that consider the capitalization of the spatial healthcare accessibility to elders into property prices. In this ageing trend across the globe, although all the accessibility to medical resources should be equally critical, the application of spatial quantile regression revealed residents’ inconsistent tendency against semi-obnoxious ambulances. It provides a different perspective in defining the importance of healthcare accessibility in neighbourhoods.

Measures of Spatial and Demographic Disparities in Access to Urban Green Space in Harbin, China

Access to urban green space (UGS) is associated with the enhancement of health and disparities in access generate issues of spatial equity and socioenvironmental justice. The aim of this study is to measure spatial accessibility and investigate access disparities to UGSs in urban areas of Harbin, China. A Gaussian-based two-step floating catchment area method and spatial autocorrelation analysis were used to measure the accessibility and evaluate its distribution patterns in residential tracts. Bivariate correlation was employed to examine the statistical relations between demographic characteristics of residential tracts and green space access. The results show that most residential tracts have minimal green space access within walking distance, while a few have limited access within cycling distance. Additionally, spatial disparities were found with low-accessibility tracts clustering in the center of the city, while high-accessibility tracts were located in northern and southern suburbs. Demographic disparities were also identified in the study: females have less access to UGS than males, areas with a high birth rate generally have more access, and population density is negatively associated with UGS access. The findings not only indicate that Harbin has an uneven distribution and disproportionate provision of UGS for urban residents but also identify which areas and population groups within the city are disadvantaged in access to UGS and thus provide suggestions for future construction and provision of UGS.

Mapping Access to Affordable Early Childhood Education and Care: Methodology and Application to Community Advocacy

Accessible and affordable early childhood care and education (ECE) is crucial to child, family, and community well-being. High quality ECE programs set the stage for lifelong learning, health, and overall well-being and yield a high rate of return on public investment. Equitable access to ECE remains an intractable challenge in the U.S. and elsewhere. We used spatial analysis to create a single micro-level indicator of ECE affordability for an urban county. This indicator combined information on supply (number of nearby sets), demand (number of children competing for these seats), and cost burden (cost as a percentage of median family income). We measured and mapped the affordability of programs within a 3-mile driving distance of a prototypical family home using a two-step floating catchment area method. Overall, affordability was low, with only 14% of young children having access to ECE that met the federal affordability threshold. Although affordability was inversely related to neighborhood income, not all low-income areas were under-resourced. The ECE affordability indicator can arm community advocates and help policymakers identify inequities and direct resources to the highest-need communities. The computational procedures and mapping techniques applied are flexible and can be scaled up to visualize inequities across large areas (e.g., a province or state), or used at a micro level to identify where in a community a new childcare center would have the most impact.

Urban Public Green Space Equity against the Context of High-Speed Urbanization in Wuhan, Central China

This study examines the relationship between equity of public green space and urban expansion/sprawl under high-speed urbanization. Equity of urban public green space indicates the degree to which urban public green spaces are distributed spatially in an equal way, with regard to the spatial variation of residents’ “need” for green space. In emerging economies such as China, especially in developing or underdeveloped cities such as Wuhan, central China, rapid urban growth challenges the capacity of the state to provide infrastructure and services for its urbanites equally. In order to research the relationship between industrial development and green space equity under the background of rapid urbanization, the use of quantitative methods to more accurately measure the degree of spatial inequality is essential. In this study, the accessibility of urban public green space in Wuhan is examined based on the two-step floating catchment area method (2SFCA) method at multilevel radius; the urban public green space accessibility of Wuhan in 2013 and 2016 are acquired, and the link between changes in accessibility of urban public green spaces and urban expansion in Wuhan is discussed. It is found that industrial development takes precedence over green space. With its vigorous development, industrial land attracts increasing population, resulting in the drastic decline of the service capacity of green spaces, which is not conducive to the long-term development of the city.

Measuring Spatial Accessibility of Urban Fire Services Using Historical Fire Incidents in Nanjing, China

The measurement of spatial accessibility of fire services is a key task in enhancing fire response efficiency and minimizing property losses and deaths. Recently, the two-step floating catchment area method and its modified versions have been widely applied. However, the circle catchment areas used in these methods are not suitable for measuring the accessibility of fire services because each fire station is often responsible for the fire incidents within its coverage. Meanwhile, most existing methods take the demographic data and their centroids of residential areas as the demands and locations, respectively, which makes it difficult to reflect the actual demands and locations of fire services. Thus, this paper proposes a fixed-coverage-based two-step floating catchment area (FC2SFCA) method that takes the fixed service coverage of fire stations as the catchment area and the locations and dispatched fire engines of historical fire incidents as the demand location and size, respectively, to measure the spatial accessibility of fire services. Using a case study area in Nanjing, China, the proposed FC2SFCA and enhanced two-step floating catchment area (E2SFCA) are employed to measure and compare the spatial accessibility of fire incidents and fire stations. The results show that (1) the spatial accessibility across Nanjing, China is unbalanced, with relatively high spatial accessibility in the areas around fire stations and the southwest and northeast at the city center area and relatively low spatial accessibility in the periphery and boundary of the service coverage areas and the core of the city center; (2) compared with E2SFCA, FC2SFCA is less influenced by other fire stations and provides greater actual fire service accessibility; (3) the spatial accessibility of fire services is more strongly affected by the number of fire incidents than firefighting capabilities, the area of service coverage, or the average number of crossroads (per kilometer). Suggestions are then made to improve the overall spatial access to fire services.

Spatial Accessibility Analysis of Parks with Multiple Entrances Based on Real-Time Travel: The Case Study in Beijing

Parks are an important component of the green infrastructure in cities. They provide multiple benefits for residents’ life. Due to the uneven spatial distribution of parks, it is necessary to evaluate the spatial disparity about residents’ access to parks. The two-step floating catchment area method is suitable for measuring the accessibility of urban parks. However, few studies have noticed the representative of entrances of parks, especially adding them into the process of accessibility measurements. The floating catchment area is often determined by road speed and empirical travel time. In this article, the impact of multi-entrances of the park will be considered and real-time travel time is used in calculating accessibility. In a case of multi-entrance parks in Beijing, the average travel time of the sub-district is calculated, and with the support of the modified method, the spatial accessibilities of car driving, public transport and car-public transport mixed travel modes are obtained. The results show that the time–space compression effect of car driving is more obvious and the mixed travel mode presents the advantage of high accessibility index. This study has a theoretical and practical value for urban planning, such as advising urban planners on the siting of green park space.

Spatial accessibility to kindergartens using a spectrum combinational approach: Case study of Shanghai using cellphone data

Spatial accessibility to kindergartens is a critical issue related to the transport safety of children. Young children should be escorted to kindergartens by adults, and trips to kindergartens are occasionally dependent on parents’ home–work trips because parents may escort their children to kindergartens en route to work. Many types of school trip can be categorized into two main types: “Home–School” and “Home–School–Work” trips. However, existing studies have tended to focus on only one type of school trip and have disregarded the other type in the assessment of accessibility. The present study examines accessibility to kindergartens by considering both types of school trips. The basic two-step floating catchment area method is used to measure the accessibility of “Home–School” trips and the commuter-based two-step floating catchment area is used for “Home–School–Work” trips. This study proposes a spectrum combinational approach, which combines both types of trips according to their actual percentages, to provide a realistic assessment of accessibility to kindergartens. An empirical study is conducted in Shanghai by combining cellphone big data and traditional data from a census. Results indicate that, compared with the spectrum combinational approach, the inequality of accessibility would be underestimated if we only focus on “Home–School” trips in the measurement of accessibility, but overestimated if we only focus on “Home–School–Work” trips. The proposed spectrum combinational approach, by modifying the trip assumptions on which accessibility evaluation is based, constitutes a novel and more realistic accessibility measurement of spatial accessibility to kindergartens.

Examining geographical accessibility to multi-tier hospital care services for the elderly: A focus on spatial equity

BackgroundWith the rapid demographic shift towards an ageing society, it is a concerted effort to facilitate elderly's access to healthcare in order to maintain and improve their quality of life. In China, hospital care services dominate the healthcare market, which requires a better understanding of accessibility to hospitals in order to rationally allocate resources in spatial and land use planning. However, little attention has been paid to analysing the geographical accessibility to hospitals specific to the elderly population. ObjectivesThe objective of this study is to examine the spatial access to multi-tier – primary, secondary, and tertiary – hospital care services for older adults with an explicit focus on equity – the (un)even distribution of geographical accessibility. MethodsBuilding on the revealed travel patterns of elderly's medical trips, this study measures the level of accessibility at the sub-district level and assesses the inter- and intra-district disparities in Nanjing, China. To this end, we draw on the city's GIS database and the 2015 Nanjing Travel Survey. A two-step floating catchment area method was utilised to measure accessibility and the Gini coefficient was applied to show inequity. ResultsIt is found that spatial distribution plays a significant role in the accessibility to hospital services. Upper-tier hospitals are more aggregated and thus more unevenly accessible than the lower-tiers. In addition, accessibility to different tiers of hospitals varies greatly throughout the city, with pockets of deprived access identified on the outskirts. Imbalance and inequality of access to hospitals are also present within districts, displaying an increasing trend from the city centre to periphery. ConclusionsThese empirical findings provide insights for health interventions in order to improve equitable access and rational allocation of health resources. This paper also bears relevance for strategically advancing the hierarchical healthcare systems in China from a geographical perspective.

Measuring accessibility to hospitals by public transport: An assessment of eight Canadian metropolitan regions

IntroductionThe ability to access healthcare services has long been considered a ‘right’ by Canadian citizens and is protected as such under the Canada Health Act. However, socio-spatial factors can limit access to healthcare services, especially for vulnerable populations. This paper aims to quantify the spatial accessibility to healthcare services by public transport across eight major Canadian metropolitan areas and compare accessibility to healthcare across vulnerable population groups. This is the first study, to the authors’ knowledge, to conduct an assessment of accessibility to hospitals by public transport across multiple metropolitan regions in Canada, thereby allowing to identify common trends, challenges, as well as knowledge gaps. MethodsSpatial accessibility to general medical and surgical hospitals by public transport was measured through a two-step floating catchment area method, considering both service-to-population ratios and travel time to these health services. For each metropolitan area, the average accessibility of all census tracts and the average accessibility of the 20% most vulnerable census tracts were calculated. To quantify vertical equity, an indicator was subsequently developed using the Spearman’s rank correlation coefficient between accessibility and vulnerability. Main findingsWithin metropolitan areas (except for Vancouver), residents of vulnerable census tracts generally have greater access to hospitals by public transport. Yet, larger metropolitan areas (Calgary, Toronto-Hamilton, and Vancouver) tend to underperform in terms of vertical equity and average accessibility. In line with this, vulnerable census tracts in these metropolitan areas are characterized by the lowest levels of accessibility compared to vulnerable census tracts in the other metropolitan areas. ConclusionThis research highlights the challenges associated with the suburbanization of poverty in large Canadian metropolitan regions and the need to provide efficient public transport services to reach hospitals located in the periphery. It also shed lights on the necessity to conduct more empirical research to inform the implementation of guidelines in terms of accessibility to healthcare in Canada. This study is of relevance to researchers, planners and policy-makers wishing to improve accessibility to healthcare, especially for vulnerable populations.

The Effect of Spatial Access to Primary Care on Potentially Avoidable Hospitalizations of the Elderly: Evidence from Chishui City, China

Potentially avoidable hospitalizations are associated with high and rising costs, and they have been widely considered as important performance indicators of the healthcare system, particularly in primary care. This study explored the relationship between spatial access to primary care and potentially avoidable hospitalizations of the elderly based on data from Chishui City, China, from 2014 to 2017. The enhanced two-step floating catchment area method was used to measure spatial access to care, while the relationship was estimated by a two-level logistic regression model with random effects, controlling for individual and household characteristics. We found a significantly negative association between potentially avoidable hospitalizations and spatial access to primary care, showing that the improvement of spatial access to primary care for the elderly would significantly reduce their potentially avoidable hospitalizations. Our results emphasized that the strategies to promote qualified, adequate and appropriate spatial distribution of primary care would substantially improve the healthcare system performance in China, also providing implications for other developing countries facing similar challenges.

A multi-mode Gaussian-based two-step floating catchment area method for measuring accessibility of urban parks

Parks play a vital role in promoting urban livability and public health; however, the traditional accessibility mode neglect non-spatial factors and spatial equity, Thus, it has significant theoretical and practical implications to explore parks accessibility using more sophisticated accessibility models, under the framework of spatial equity. Based on network analysis, different trip modes (walking, public transport, and car modes) and park attractiveness coefficients were integrated into a Gaussian-based 2SFCA model, and park accessibility in the 10-min, 15-min, and 20-min scenarios was analyzed and compared with a single-mode model. The spatial mismatch between park accessibility and population density was also explored by bivariate local Moran's I statistic. Results show that: 1. The landscapes of park accessibility are spatial heterogenous and varied with temporal-spatial scale. With the increase of catchment size, the mean value and standard deviation of park accessibility decreases. 2. The traditional single-mode model will overestimate park accessibility while the multi-modes model can provide more realistic evaluation and offer better guidance for urban park planning. The multi-mode model can also get smoother and homogeneous results. 3. The spatial relationships between park accessibility and population density are divided into a positive match, negative match, positive mismatch, negative mismatch, and non-significant. This paper can provide some improvement to studies that did not consider the impact of trip modes and park attributes on accessibility and spatial equity.

Measuring Accessibility of Healthcare Facilities for Populations with Multiple Transportation Modes Considering Residential Transportation Mode Choice

Accessibility research of healthcare facilities is developing towards multiple transportation modes (MTM), which are influenced by residential transportation choices and preferences. Due to differences in travel impact factors such as traffic conditions, origin location, distance to the destination, and economic cost, residents’ daily travel presents different residential transportation mode choices (RTMC). The purpose of our study was to measure the spatial accessibility of healthcare facilities based on MTM considering RTMC (MTM-RTMC). We selected the gravity two-step floating catchment area method (G2SFCA) as a fundamental model. Through the single transportation mode (STM), MTM, and MTM-RTMC, three aspects used to illustrate and redesign the G2SFCA, we obtained the MTM-RTMC G2SFCA model that integrates RTMC probabilities and the travel friction coefficient. We selected Nanjing as the experimental area, used route planning data of four modes (including driving, walking, public transportation, and bicycling) from a web mapping platform, and applied the three models to pediatric clinic services to measure accessibility. The results show that the MTM-RTMC mechanism is to make up for the traditional estimation of accessibility, which loses sight of the influence of residential transportation choices. The MTM-RTMC mechanism that provides a more realistic and reliable way can generalize to major accessibility models and offers preferable guidance for policymakers.

Role of Area-Level Access to Primary Care on the Geographic Variation of Cardiometabolic Risk Factor Distribution: A Multilevel Analysis of the Adult Residents in the Illawarra-Shoalhaven Region of NSW, Australia.

Background: Access to primary care is important for the identification, control and management of cardiometabolic risk factors (CMRFs). This study investigated whether differences in geographic access to primary care explained area-level variation in CMRFs. Methods: Multilevel logistic regression models were used to derive the association between area-level access to primary care and seven discrete CMRFs after adjusting for individual and area-level co-variates. Two-step floating catchment area method was used to calculate the geographic access to primary care for the small areas within the study region. Results: Geographic access to primary care was inversely associated with low high density lipoprotein (OR 0.94, CI 0.91–0.96) and obesity (OR 0.91, CI 0.88–0.93), after adjusting for age, sex and area-level disadvantage. The intra-cluster correlation coefficient (ICCs) of all the fully adjusted models ranged between 0.4–1.8%, indicating low general contextual effects of the areas on CMRF distribution. The area-level variation in CMRFs explained by primary care access was ≤10.5%. Conclusion: The findings of the study support proportionate universal interventions for the prevention and control of CMRFs, rather than any area specific interventions based on their primary care access, as the contextual influence of areas on all the analysed CMRFs were found to be minimal. The findings also call for future research that includes other aspects of primary care access, such as road-network access, financial affordability and individual-level acceptance of the services in order to gain an overall picture of the area-level contributing role of primary care on CMRFs in the study region.

Scenario Analyses Using an Accessibility Index Based on the Two-Step Floating Catchment Area Method: Case Study of Daycare Centers in Takatsuki, Osaka Prefecture

Scenario Analyses Using an Accessibility Index Based on the Two-Step Floating Catchment Area Method: Case Study of Daycare Centers in Takatsuki, Osaka Prefecture

How spatial accessibility to colonoscopy affects diagnostic adherences and adverse intestinal outcomes among the patients with positive preliminary screening findings.

BackgroundColonoscopy is an important procedure for early colorectal cancer (CRC) detection, however, patients with positive preliminary screening results in China may not seek for colonoscopy to confirm the diagnosis. We evaluated the spatial accessibility of colonoscopy among the residents with positive preliminary screening results in Guangzhou, China, and investigated how colonoscopy accessibility was associated with the population adherence and adverse intestinal outcomes.MethodsThis study was based on the Guangzhou community‐based CRC screening program. Spatial accessibility was measured using three metrics including travel time from home to nearest colonoscopy hospital, physician‐to‐population ratio (PPR) and accessibility indicator estimated with enhanced two‐step floating catchment area method (E2SFCA). We used Cox regression and logistic regression to assess the association of colonoscopy accessibility with population adherence and adverse intestinal outcomes, respectively.ResultsA total of 34 606 people were identified with positive preliminary screening findings. Central areas were reported with higher E2SFCA scores, higher PPR and less travel time. The model adjusting for potential individual level confounders found that PPR > 50 (Hazard Ratio (HR) = 1.88, 95% Confidence Interval (CI): 1.79‐1.97) and higher scores of E2SFCA (HR = 3.78, 95% CI: 2.07‐6.92) were associated with increased adherence, although estimates were not significant in the model adjusting for both individual and district‐level confounders. For adverse intestinal outcomes, the final multilevel logistic model suggested a lower risk of intestinal lesions among the residents in areas with PPR > 50 (Odds Ratio (OR) = 0.49, 95% CI: 0.24‐0.99) and higher scores of E2SFCA (OR = 0.20, 95% CI: 0.05‐0.82).ConclusionSignificant inequality of colonoscopy accessibility was observed across Guangzhou. The increased incidence of intestinal lesions was associated with spatial inequalities of medical resources. Policies against the spatial inequality in medical resources should be developed.

Spatial access to primary care providers and colorectal cancer-specific survival in Cook County, Illinois.

BackgroundSpatial access to primary care has been associated with late‐stage and fatal breast cancer, but less is known about its relation to outcomes of other screening‐preventable cancers such as colorectal cancer. This population‐based retrospective cohort study examined whether spatial access to primary care providers associates with colorectal cancer‐specific survival.MethodsApproximately 26 600 incident colorectal cancers diagnosed between 2000 and 2008 in adults residing in Cook County, Illinois were identified through the state cancer registry and georeferenced to the census tract of residence at diagnosis. An enhanced two‐step floating catchment area method measured tract‐level access to primary care physicians (PCPs) in the year of diagnosis using practice locations obtained from the American Medical Association. Vital status and underlying cause of death were determined using the National Death Index. Fine‐Gray proportional subdistribution hazard models analyzed the association between tract‐level PCP access scores and colorectal cancer‐specific survival after accounting for tract‐level socioeconomic status, case demographics, tumor characteristics, and other factors.ResultsIncreased tract‐level access to PCPs was associated with a lower risk of death from colorectal cancer (hazard ratio [HR], 95% confidence interval [CI]) = 0.87 [0.79, 0.96], P = .008, highest vs lowest quintile), especially among persons diagnosed with regional‐stage tumors (HR, 95% CI = 0.80 [0.69, 0.93], P = .004, highest vs lowest quintile).ConclusionsSpatial access to primary care providers is a predictor of colorectal cancer‐specific survival in Cook County, Illinois. Future research is needed to determine which areas within the cancer care continuum are most affected by spatial accessibility to primary care such as referral for screening, accessibility of screening and diagnostic testing, referral for treatment, and access to appropriate survivorship‐related care.

Geographical accessibility of community social services and incidence of self-harm

ObjectiveThe study aimed to explore the association between area-based coverage of community services and the incidence of self-harm, which will provide an evaluation framework for the support of self-harm. MethodsEnhanced two-Step floating catchment area method was used to estimate the centersto- population ratio and geographical accessibility adjusted by a distance-decay function. Spearman's rank coefficient was used to examine the association between the self-harm rate and adjusted accessibility index. ResultsThere was a significant negative correlation between the accessibility index and selfharm rate in youth (rho = −0.87, P < 0.01) and older adults (rho = −0.87, P < 0.01). The survival curves showed no relationship between self-harm repetition and service accessibility in youth or older adults. ConclusionsThe uneven spatial accessibility of community social service centers and the independence between spatial accessibility and self-harm highlights the need to explore personal barriers to community service utilization.

Maximum equity in access of top-tier general hospital resources in China: a spatial optimisation model

BackgroundThe health-care system in China has improved substantially, but regional disparity in the allocation of health-care resources remains a crucial problem, especially for high-quality health-care resources. We aimed to explore the reallocation of the top-tier general hospital beds to achieve higher equity of spatial accessibility in China. MethodsWe collected the supply data from the Chinese National Health Commission. 550 top-tier general hospitals in 2015 were included in our study. We obtained the population data from the WorldPop database, and aggregated to the county-level data. We used the two-step floating catchment area method to measure spatial accessibility to top-tier general hospitals. Then, we established a spatial optimisation model to minimise the variance of spatial accessibility of 2853 counties, and the quadratic programming was used to compute the optimised beds of each hospital. Finally, we compared the current and optimised spatial reallocation policy in terms of SD of spatial accessibility. FindingsThe optimised policy achieved equal spatial accessibility with lower SD from 0·592 to 0·356. The SD of spatial accessibility decreased from 0·571 to 0·322 for eastern areas, from 0·598 to 0·339 for central areas, and from 0·593 to 0·340 for western areas. However, there were substantial differences in average spatial accessibility in different areas. The average spatial accessibility for eastern areas increased from 0·52 to 0·57, whereas it decreased from 0·49 to 0·45 for central areas and from 0·36 to 0·28 for western areas. The optimised number of beds in the east was 400 521, central was 237 974, and west was 163 672. The gaps between the current and optimised results suggested that more beds needed to be allocated to the east, whereas the beds in central and western areas were oversupplied. InterpretationOur findings implied that the central and western areas need to reduce the bed supplies under the condition that the total beds remain unchanged. To promote equal accessibility, health policies should be different for different areas. More resources are needed for the east, whereas improving the road network and building more hospitals would help to improve spatial accessibility in central and western areas. FundingThe National Nature Science Foundation of China (71874116) and China Medical Board (17-276).