title: Factors associated with closures of emergency departments in the United States.
abstract: BACKGROUND
  Between 1998 and 2008, the number of hospital-based emergency departments (EDs) in the United States declined, while the number of ED visits increased, particularly visits by patients who were publicly insured and uninsured. Little is known about the hospital, community, and market factors associated with ED closures. Federal law requiring EDs to treat all in need regardless of a patient's ability to pay may make EDs more vulnerable to the market forces that govern US health care.
  
  
  OBJECTIVE
  To determine hospital, community, and market factors associated with ED closures.
  
  
  METHODS
  Emergency department and hospital organizational information from 1990 through 2009 was acquired from the American Hospital Association (AHA) Annual Surveys (annual response rates ranging from 84%-92%) and merged with hospital financial and payer mix information available through 2007 from Medicare hospital cost reports. We evaluated 3 sets of risk factors: hospital characteristics (safety net [as defined by hospitals caring for more than double their Medicaid share of discharges compared with other hospitals within a 15-mile radius], ownership, teaching status, system membership, ED size, case mix), county population demographics (race, poverty, uninsurance, elderly), and market factors (ownership mix, profit margin, location in a competitive market, presence of other EDs).
  
  
  METHODS
  All general, acute, nonrural, short-stay hospitals in the United States with an operating ED anytime from 1990-2009.
  
  
  METHODS
  Closure of an ED during the study period.
  
  
  RESULTS
  From 1990 to 2009, the number of hospitals with EDs in nonrural areas declined from 2446 to 1779, with 1041 EDs closing and 374 hospitals opening EDs. Based on analysis of 2814 urban acute-care hospitals, constituting 36,335 hospital-year observations over an 18-year study interval (1990-2007), for-profit hospitals and those with low profit margins were more likely to close than their counterparts (cumulative hazard rate based on bivariate model, 26% vs 16%; hazard ratio [HR], 1.8; 95% confidence interval [CI], 1.5-2.1, and 36% vs 18%; HR, 1.9; 95% CI, 1.6-2.3, respectively). Hospitals in more competitive markets had a significantly higher risk of closing their EDs (34% vs 17%; HR, 1.3; 95% CI, 1.1-1.6), as did safety-net hospitals (10% vs 6%; HR, 1.4; 95% CI, 1.1-1.7) and those serving a higher share of populations in poverty (37% vs 31%; HR, 1.4; 95% CI, 1.1-1.7).
  
  
  CONCLUSIONS
  From 1990 to 2009, the number of hospital EDs in nonrural areas declined by 27%, with for-profit ownership, location in a competitive market, safety-net status, and low profit margin associated with increased risk of ED closure.
authors.affiliation: Department of Emergency Medicine, University of California, San Francisco, CA, USA. renee.hsia@ucsf.edu
authors.forename: Renee Y
authors.initials: RY
authors.lastname: Hsia
authors.forename: Arthur L
authors.initials: AL
authors.lastname: Kellermann
authors.forename: Yu-Chu
authors.initials: YC
authors.lastname: Shen
mesh_terms: D000368:Aged; D000573:American Hospital Association; D003625:Data Collection; D003953:Diagnosis-Related Groups; D004465:Economic Competition; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D006271:Health Facility Closure / Q000191:economics / Q000706:statistics & numerical data*; D016304:Hospitals, Private / Q000191:economics / Q000706:statistics & numerical data*; D006786:Hospitals, Urban / Q000191:economics / Q000706:statistics & numerical data; D006801:Humans; D008484:Medicaid / Q000191:economics; D017057:Medically Uninsured; D006278:Medicare / Q000191:economics; D010067:Ownership; D011203:Poverty; D017664:Uncompensated Care / Q000191:economics; D014481:United States