title: The New Injury Severity Score: a more accurate predictor of in-hospital mortality than the Injury Severity Score.
abstract: OBJECTIVE
  The purpose of this study was to determine whether the New Injury Severity Score (NISS) is a better predictor of mortality than the Injury Severity Score (ISS) in general and in subgroups according to age, penetrating trauma, and body region injured.
  
  
  METHODS
  The study population consisted of 24,263 patients from three urban Level I trauma centers in the province of Quebec, Canada. Discrimination and calibration of NISS and ISS models were compared using receiver operator characteristic (ROC) curves and Hosmer-Lemeshow statistics.
  
  
  RESULTS
  NISS showed better discrimination than ISS (area under the ROC curve = 0.827 vs. 0.819; p = 0.0006) and improved calibration (Hosmer-Leme-show = 62 vs. 112). The advantage of the NISS over the ISS was particularly evident among patients with head/neck injuries (area under the ROC curve = 0.819 vs. 0.784; p < 0.0001; Hosmer-Lemeshow = 59 vs. 350).
  
  
  CONCLUSIONS
  The NISS is a more accurate predictor of in-hospital death than the ISS and should be chosen over the ISS for case-mix control in trauma research, especially in certain subpopulations such as head/neck-injured patients.
authors.affiliation: Centre hospitalier affilié universitaire de Québec, Enfant-Jésus Hospital, Quebec City, Quebec, Canada. drlavoa@cha.quebec.qc.ca
authors.forename: André
authors.initials: A
authors.lastname: Lavoie
authors.forename: Lynne
authors.initials: L
authors.lastname: Moore
authors.forename: Natalie
authors.initials: N
authors.lastname: LeSage
authors.forename: Moishe
authors.initials: M
authors.lastname: Liberman
authors.forename: John S
authors.initials: JS
authors.lastname: Sampalis
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D019540:Area Under Curve; D006259:Craniocerebral Trauma / Q000401:mortality; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D008875:Middle Aged; D011792:Quebec / Q000453:epidemiology; D012372:ROC Curve; D012042:Registries; D012680:Sensitivity and Specificity; D013124:Spinal Injuries / Q000401:mortality; D014947:Wounds and Injuries / Q000401:mortality*