title: Spatial accessibility of primary care pediatric services in an urban environment: association with asthma management and outcome.
abstract: BACKGROUND
  Disadvantaged urban children with asthma depend heavily on emergency departments (EDs) for episodic care. We hypothesized that among an urban population of children with asthma, higher spatial accessibility to primary care pediatric services would be associated with (1) more scheduled primary care visits for asthma, (2) better longitudinal asthma management, and (3) fewer unscheduled visits for asthma care.
  
  
  METHODS
  We enrolled children aged 12 months to 17 years, inclusive, who sought acute asthma care in an urban pediatric ED. Eligibility criteria included a history of unscheduled visits for asthma in the previous year. We collected comprehensive data on each participant's asthma medical management and prior health care utilization. In addition, we calculated each participant's spatial accessibility to primary care pediatric services, reported as a provider-to-population ratio at their place of residence. Patients then were stratified by their spatial accessibility to care and compared with respect to measures of medical management and health care utilization.
  
  
  RESULTS
  Among the 411 eligible participants, the spatial accessibility of primary care ranged from 7.4 to 350.2 full-time pediatric providers per 100,000 children <18 years of age, with a mean of 57.7 +/- 40.0. Patients in the middle and highest tertiles of spatial accessibility made significantly more scheduled visits for asthma care than patients in the lowest tertile. There were no differences among tertiles of accessibility with respect to asthma management or with respect to unscheduled visits for asthma care.
  
  
  CONCLUSIONS
  Within this highly urban, largely disadvantaged and minority population of children with chronic asthma, patients with higher spatial accessibility to primary care services made significantly more scheduled visits for asthma care.
authors.affiliation: Division of Emergency Medicine, Children's National Medical Center, George Washington University School of Medicine and Health Sciences, 111 Michigan Ave NW, Washington, DC 20010, USA. steach@cnmc.org
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Teach
authors.forename: Mark F
authors.initials: MF
authors.lastname: Guagliardo
authors.forename: Ellen F
authors.initials: EF
authors.lastname: Crain
authors.forename: Robert J
authors.initials: RJ
authors.lastname: McCarter
authors.forename: Deborah M
authors.initials: DM
authors.lastname: Quint
authors.forename: Cheng
authors.initials: C
authors.lastname: Shao
authors.forename: Jill G
authors.initials: JG
authors.lastname: Joseph
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000628:therapy*; D002391:Catchment Area, Health; D002648:Child; D002662:Child Health Services / Q000706:statistics & numerical data / Q000600:supply & distribution*; D002675:Child, Preschool; D004219:District of Columbia; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D006297:Health Services Accessibility / Q000706:statistics & numerical data*; D006801:Humans; D007223:Infant; D008297:Male; D011320:Primary Health Care / Q000706:statistics & numerical data*; D014481:United States; D019037:Urban Health Services / Q000706:statistics & numerical data / Q000600:supply & distribution*; D014505:Urban Population; D035862:Vulnerable Populations; D000078329:Workforce