title: Spatial decision on allocating automated external defibrillators (AED) in communities by multi-criterion two-step floating catchment area (MC2SFCA).
abstract: The occurrence of out-of-hospital cardiac arrest (OHCA) is a critical life-threatening event which frequently warrants early defibrillation with an automated external defibrillator (AED). The optimization of allocating a limited number of AEDs in various types of communities is challenging. We aimed to propose a two-stage modeling framework including spatial accessibility evaluation and priority ranking to identify the highest gaps between demand and supply for allocating AEDs.
  
  
  
  In this study, a total of 6135 OHCA patients were defined as demand, and the existing 476 publicly available AEDs locations and 51 emergency medical service (EMS) stations were defined as supply. To identify the demand for AEDs, Bayesian spatial analysis with the integrated nested Laplace approximation (INLA) method is applied to estimate the composite spatial risks from multiple factors. The population density, proportion of elderly people, and land use classifications are identified as risk factors. Then, the multi-criterion two-step floating catchment area (MC2SFCA) method is used to measure spatial accessibility of AEDs between the spatial risks and the supply of AEDs. Priority ranking is utilized for prioritizing deployment of AEDs among communities because of limited resources.
  
  
  
  Among 6135 OHCA patients, 56.85 % were older than 65 years old, and 79.04 % were in a residential area. The spatial distribution of OHCA incidents was found to be concentrated in the metropolitan area of Kaohsiung City, Taiwan. According to the posterior mean estimated by INLA, the spatial effects including population density and proportion of elderly people, and land use classifications are positively associated with the OHCA incidence. Utilizing the MC2SFCA for spatial accessibility, we found that supply of AEDs is less than demand in most areas, especially in rural areas. Under limited resources, we identify priority places for deploying AEDs based on transportation time to the nearest hospital and population size of the communities.
  
  
  
  The proposed method will be beneficial for optimizing resource allocation while considering multiple local risks. The optimized deployment of AEDs can broaden EMS coverage and minimize the problems of the disparity in urban areas and the deficiency in rural areas.
authors.affiliation: Research Center for Humanity and Social Sciences, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei, 115, Taiwan.
authors.forename: Bo-Cheng
authors.initials: BC
authors.lastname: Lin
authors.affiliation: Division of Trauma, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan. kmutrauma@gmail.com.|Department of Emergency Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, 100 Tzyou 1st Road, Kaohsiung, 807, Taiwan. kmutrauma@gmail.com.
authors.forename: Chao-Wen
authors.initials: CW
authors.lastname: Chen
authors.affiliation: Research Center for Humanity and Social Sciences, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei, 115, Taiwan.
authors.forename: Chien-Chou
authors.initials: CC
authors.lastname: Chen
authors.affiliation: Research Center for Humanity and Social Sciences, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei, 115, Taiwan.|Department of Geomatics, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Chiao-Ling
authors.initials: CL
authors.lastname: Kuo
authors.affiliation: Research Center for Humanity and Social Sciences, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei, 115, Taiwan.|Institute of History and Philology, Academia Sinica, Taipei, Taiwan.
authors.forename: I-Chun
authors.initials: IC
authors.lastname: Fan
authors.affiliation: Department of Health, Kaohsiung City Government, Kaohsiung, Taiwan.|Department of Public Health, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors.forename: Chi-Kung
authors.initials: CK
authors.lastname: Ho
authors.affiliation: Fire Bureau, Kaohsiung City Government, Kaohsiung, Taiwan.
authors.forename: I-Chuan
authors.initials: IC
authors.lastname: Liu
authors.affiliation: Research Center for Humanity and Social Sciences, Academia Sinica, 128 Academia Road, Section 2, Nankang, Taipei, 115, Taiwan. dachianpig@gmail.com.
authors.forename: Ta-Chien
authors.identifier: 0000-0002-1685-783X
authors.initials: TC
authors.lastname: Chan
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001499:Bayes Theorem; D002391:Catchment Area, Health / Q000706:statistics & numerical data*; D002648:Child; D002675:Child, Preschool; D047548:Defibrillators / Q000600:supply & distribution*; D005260:Female; D015276:Health Care Rationing / Q000379:methods; D006301:Health Services Needs and Demand; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000453:epidemiology*; D017678:Sex Distribution; D012959:Socioeconomic Factors; D062206:Spatial Analysis; D013624:Taiwan; D055815:Young Adult
keywords: Basic statistical area; Bayesian analysis; Out-of-hospital cardiac arrest; Priority ranking; Zero-inflated Poisson model