title: Asthma population management: development and validation of a practical 3-level risk stratification scheme.
abstract: OBJECTIVE
  To define and validate a practical risk stratification scheme based on administrative data for use in identifying patients at high, medium, and low risk of requiring emergency hospital care for asthma.
  
  
  METHODS
  Retrospective cohort.
  
  
  METHODS
  Predictors in 1999 were evaluated in relation to 2000 asthma emergency hospital care (any asthma hospitalization or emergency department visit) in a training set (n = 8789, 2000 emergency hospital care = 5.5%) and a testing set (n = 6104, 2000 emergency hospital care = 7.9%). Logistic regression was used to assign risk points in the training set, and positive and negative predictive values, sensitivities, and specificities were calculated in the training and testing sets.
  
  
  RESULTS
  High risk was defined as asthma emergency hospital care in the previous year or use of >14 beta-agonist canisters and oral corticosteroid use; medium risk was defined as no emergency hospital care but use of either >14 beta-agonist canisters or oral corticosteroids; and low risk was defined as none of the above. For the high-risk groups in the training and testing sets, positive predictive values were 12.9% and 22.0%, sensitivities were 24.8% and 25.4%, specificities were 90.3% and 92.0%, and negative predictive values were 95.4% and 93.2%, respectively. The medium-risk groups identified another 32.6% of patients in the training set and 28.3% in the testing set requiring subsequent asthma emergency hospital care.
  
  
  CONCLUSIONS
  This simple risk stratification scheme is useful for identifying patients from administrative data who are at increased risk of experiencing emergency hospital care for asthma.
authors.affiliation: Department of Allergy, Kaiser-Permanente Medical Center, San Diego, CA 92111, USA. michael.x.schatz@kp.org
authors.forename: Michael
authors.initials: M
authors.lastname: Schatz
authors.forename: Randy
authors.initials: R
authors.lastname: Nakahiro
authors.forename: Christine H
authors.initials: CH
authors.lastname: Jones
authors.forename: Richard M
authors.initials: RM
authors.lastname: Roth
authors.forename: Anita
authors.initials: A
authors.lastname: Joshua
authors.forename: Diana
authors.initials: D
authors.lastname: Petitti
mesh_terms: D000293:Adolescent; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000627:therapeutic use; D000318:Adrenergic beta-Agonists / Q000627:therapeutic use; D000328:Adult; D001249:Asthma / Q000453:epidemiology* / Q000628:therapy*; D002140:California / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D019468:Disease Management; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data; D005260:Female; D006302:Health Services Research; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008329:Managed Care Programs / Q000706:statistics & numerical data; D008875:Middle Aged; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*
chemical_list: D000305:Adrenal Cortex Hormones; D000318:Adrenergic beta-Agonists