title: Validation of an algorithm to determine the primary care treatability of emergency department visits.
abstract: We propose a new claims-computable measure of the primary care treatability of emergency department (ED) visits and validate it using a nationally representative sample of Medicare data.
  
  
  
  This is a validation study using 2011-2012 Medicare claims data for a nationally representative 5% sample of fee-for-service beneficiaries to compare the new measure's performance to the Ballard variant of the Billings algorithm in predicting hospitalisation and death following an ED visit.
  
  
  
  Hospitalisation within 1 day or 1 week of an ED visit; death within 1 week or 1 month of an ED visit.
  
  
  
  The Minnesota algorithm is a strong predictor of hospitalisations and deaths, with performance similar to or better than the most commonly used existing algorithm to assess the severity of ED visits. The Billings/Ballard algorithm is a better predictor of death within 1 week of an ED visit; this finding is entirely driven by a small number of ED visits where patients appear to have been dead on arrival.
  
  
  
  The procedure-based approach of the Minnesota algorithm allows researchers to use the clinical judgement of the ED physician, who saw the patient to determine the likely severity of each visit. The Minnesota algorithm may thus provide a useful tool for investigating ED use in Medicare beneficiaries.
authors: Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota, USA.
authors: Molly Moore
authors: MM
authors: Jeffery
authors: Department of Emergency Medicine, Mayo Clinic, Rochester, Minnesota, USA.
authors: M Fernanda
authors: MF
authors: Bellolio
authors: Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, Minnesota, USA.
authors: Julian
authors: J
authors: Wolfson
authors: Division of Health Policy and Management, School of Public Health, University of Minnesota, Minneapolis, Minnesota, USA.
authors: Jean M
authors: JM
authors: Abraham
authors: Division of Health Policy and Management, School of Public Health, University of Minnesota, Minneapolis, Minnesota, USA.
authors: Bryan E
authors: BE
authors: Dowd
authors: Division of Health Policy and Management, School of Public Health, University of Minnesota, Minneapolis, Minnesota, USA.
authors: Robert L
authors: RL
authors: Kane
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D004636:Emergency Service, Hospital; D018588:Fee-for-Service Plans; D005260:Female; D017052:Hospital Mortality; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007345:Insurance Claim Review; D008297:Male; D006278:Medicare; D008875:Middle Aged; D008910:Minnesota; D011320:Primary Health Care; D013997:Time Factors; D014481:United States
keywords: ACCIDENT & EMERGENCY MEDICINE; Administrative data; GERIATRIC MEDICINE; STATISTICS & RESEARCH METHODS