title: [Validating the Adjusted Clinical Groups [ACG] case-mix system in a Spanish population setting: a multicenter study].
abstract: OBJECTIVE
  To validate the Johns Hopkins ACG case-mix system used in various primary and specialized care centers attending a defined population in Spain.
  
  
  METHODS
  A retrospective, multicenter study was carried out by applying the ACG case-mix system to the clinical records of patients attending five primary care teams and two hospitals over a 1-year period in 2005. The main measurements were dependent variables (visits, episodes, primary care costs, and total costs), and morbidity. The determination coefficient (R2; p<0.05) was used to measure the explained variability.
  
  
  RESULTS
  A total of 81,873 patients were included with a mean (standard deviation) number of 4.8 (3.5) episodes and 8.0 (8.1) visits/patient/year. The explained variance (R2) of ACG classification was 73.1% (75.5% log transformation) for episodes, 43.2% (54.0% log transformation) for visits, 19.6% (54.8% log transformation) for primary care costs, and 22.7% (48.3% log transformation) for total costs (p<0.001).
  
  
  CONCLUSIONS
  The ACG system classified a defined population on the basis of morbidity and individual resource consumption. Moreover, the ACG system was useful to assess the clinical (comorbidity) and economical information of each center.
authors.affiliation: Dirección de Planificación, Badalona Servicios Asistenciales, S.A., Badalona, Barcelona, España.
authors.forename: Antoni
authors.initials: A
authors.lastname: Sicras-Mainar
authors.forename: Ruth
authors.initials: R
authors.lastname: Navarro-Artieda
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003953:Diagnosis-Related Groups / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D012189:Retrospective Studies; D013030:Spain