title: Hospital stay as a proxy indicator for severe injury in earthquakes: a retrospective analysis.
abstract: BACKGROUND
  Earthquakes are the most violent type of natural disasters and injuries are the dominant medical problem in the early phases after earthquakes. However, likely because of poor data availability, high-quality research on injuries after earthquakes is lacking. Length of hospital stay (LOS) has been validated as a proxy indicator for injury severity in high-income settings and could potentially be used in retrospective research of injuries after earthquakes. In this study, we assessed LOS as an adequate proxy indicator for severe injury in trauma survivors of an earthquake.
  
  
  METHODS
  A retrospective analysis was conducted using a database of 1,878 injured patients from the 2008 Wenchuan earthquake. Our primary outcome was severe injury, defined as a composite measure of serious injury or resource use. Secondary outcomes were serious injury and resource use, analysed separately. Non-parametric receiver operating characteristics (ROC) and area under the curve (AUC) analysis was used to test the discriminatory accuracy of LOS when used to identify severe injury. An 0.7<AUC<0.8 was defined as adequate.
  
  
  RESULTS
  Our study shows that LOS discriminatory accuracy is poor for the primary outcome. However, LOS discriminatory accuracy is adequate for resource use, excluding critical orthopaedic interventions and debridement.
  
  
  CONCLUSIONS
  Length of hospital stay was not validated as a proxy indicator for severe injury in earthquake survivors. However, LOS was found to be a proxy for major nonorthopaedic surgery and blood transfusion. These findings can be useful for retrospective research on earthquake-injured patients when detailed hospital records are not available.
authors.affiliation: People's Hospital of Deyang City, Deyang, Sichuan province, China.
authors.forename: Lu-Ping
authors.initials: LP
authors.lastname: Zhao
authors.forename: Martin
authors.initials: M
authors.lastname: Gerdin
authors.forename: Lina
authors.initials: L
authors.lastname: Westman
authors.forename: Jose Manuel
authors.initials: JM
authors.lastname: Rodriguez-Llanes
authors.forename: Qi
authors.initials: Q
authors.lastname: Wu
authors.forename: Barbara
authors.initials: B
authors.lastname: van den Oever
authors.forename: Liang
authors.initials: L
authors.lastname: Pan
authors.forename: Manuel
authors.initials: M
authors.lastname: Albela
authors.forename: Gao
authors.initials: G
authors.lastname: Chen
authors.forename: De-Sheng
authors.initials: DS
authors.lastname: Zhang
authors.forename: Debarati
authors.initials: D
authors.lastname: Guha-Sapir
authors.forename: Johan
authors.initials: J
authors.lastname: von Schreeb
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D002648:Child; D002675:Child, Preschool; D002681:China; D004190:Disasters; D055866:Earthquakes; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D015601:Injury Severity Score; D007902:Length of Stay / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D009104:Multiple Trauma / Q000175:diagnosis* / Q000601:surgery / Q000628:therapy; D012372:ROC Curve; D012189:Retrospective Studies