Measuring Accessibility to Medical Centers in Isfahan City Using 2SFCA Method

Abstract

AbstractOne of the most important challenges facing policymakers and urban planners in recent decades is the issue of accessibility to a variety of urban services. The main purpose of this study was thecalculation of the accessibility of census blocks to medical centers using the Two-Step Floating Catchment Area (2SFCA) method in Isfahan City. In the present study, according to the conditions with and without the limitations of the accessibility radii, different types of distance decay functions were used. The results showed that the 2SFCA method with the use of the cumulative opportunity negative linear function had the highest average of correlation for calculating accessibility to medical centers in comparison with other functions. Calculation of average accessibility in the 15 main regions of Isfahan City showed that the central regions (3, 1, and 5) had the highest decrease and the marginal regions (9, 8, and 11) had the highest increase in the unlimited compared to the limited mode. In general, based on the obtained results of 2SFCA method and the calculated Gini index, the level of inequality in accessibility of census blocks to health services was high in Isfahan City and this inequality increased in terms of accessibility to both hospitals and clinics. Since the extended 2SFCA method has a high capability for assessing supply and demand, as well as catchment area, application of this method can provide a great help for managers and planners in theassessment of the population’s access to a variety of services, such as emergency services and healthcare.Keywords: spatial accessibility, 2SFCA method, distance decay function, medical centers, Isfahan IntroductionOne of the most important challenges faced by policymakers and urban planners in recent decades has been the subjct of access to a variety of urban services. Hospital and clinic centers as the most important urban facilities play an important role in serving people. handeling access to healthcare requires examining the factors, such as spatial distribution of services and demands. Distribution of healthcare centers can affect ease of accessibility for applicants. As health is the basis of social, economic, political, and cultural developments of human societies, identifying deprived areas in terms of accessibility and planning for equitable accessibility to health services for all members of society are essential. MethodologyIn the present study, the Two-Step Floating Catchment Area Method (2SFCA) was employed to calculate the access of census blocks to medical centers (hospitals and clinics) in the city of Isfahan for limited and unlimited accessibility radii. To define the most appropriate distance decay function in the 2SFCA method, the average of Pearson’s correlation coefficient between the accessibility values ​​obtained from different distance decay functions was used. The distance decay function with the highest mean correlation of accessibility values compared to other functions was determined as the most appropriate function in the 2SFCA method. Also, the Lorenz curve and Gini coefficient were applied to compare inequalities of access to medical centers in Isfahan. Results and DiscussionThe results showed that the use of the negative linear cumulative opportunity distance decay function had the highest average correlation in the accessibility values compared to other functions. In the case of limited accessibility radius, the central regions and some northwest and east areas had the highest accessibility to hospitals. In the case of unlimited radius, the central areas had the most accessibility, while accessibility decreased as the distance from these areas increased. Calculation of the average accessibility in the 15 main regions of Isfahan showed that the central (3, 1 and 5) and marginal (9, 8, and 11) regions had the highest decrease and increase in the unlimited compared to the limited mode, respectively. Also, the sensitivity analysis of accessibility to hospitals showed that Al-Zahra and Hazrat Zahra hospitals in Districts 5 and 14 had the greatest impacts on the accessibility of cesus blocks to hospital services in Isfahan City. Comparing the accessibility of census blocks to both hospitals and clinics with accessibility only to hospitals showed an increase in accessibility in the central areas of the city due to the greater concentration of clinics in those areas. However, in the case of combination of hospitals and clinics, the Gini coefficient was equal to 0.60, which showed an increase of 0.04 compared to the case of accessibility only to hospitals, which indicated that inequality was higher in the combinatorial case. ConclusionConsidering the supply and demand simultaneously, the 2SFCA method can provide a more realistic assessment of the accessibility status of census blocks to medical services. 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Keywords

• spatial accessibility
• 2sfca method
• distance decay function
• medical centers
• isfahan