title: Impact of socio-economic status on hospital length of stay following injury: a multicenter cohort study.
abstract: BACKGROUND
  Injury is second only to cardiovascular disease in terms of acute care costs in North America. One key to improving injury care efficiency is to generate knowledge on the determinants of resource use. Socio-economic status (SES) is a documented risk factor for injury severity and mortality but its impact on length of stay (LOS) for injury admissions is unknown. This study aimed to examine the relationship between SES and LOS following injury. This multicenter retrospective cohort study was based on adults discharged alive from any trauma center (2007-2012; 57 hospitals; 65,486 patients) in a Canadian integrated provincial trauma system. SES was determined using ecological indices of material and social deprivation. Mean differences in LOS adjusted for age, gender, comorbidities, and injury severity were generated using multivariate linear regression.
  
  
  RESULTS
  Mean LOS was 13.5 days. Patients in the highest quintile of material/social deprivation had a mean LOS 0.5 days (95 % CI 0.1-0.9)/1.4 days (1.1-1.8) longer than those in the lowest quintile. Patients in the highest quintiles of both social and material deprivation had a mean LOS 2.6 days (1.8-3.5) longer than those in the lowest quintiles.
  
  
  CONCLUSIONS
  Results suggest that patients admitted for traumatic injury who suffer from high social and/or material deprivation have longer acute care LOS in a universal-access health care system. The reasons behind observed differences need to be further explored but may indicate that discharge planning should take patient SES into consideration.
authors.affiliation: Department of social and preventive medicine, Laval University, Quebec, QC, Canada. Lynne.moore@fmed.ulaval.ca.|Population Health and Optimal Health Practices Research Unit, Trauma - Emergency - Critical Care Medicine, Centre de Recherche du Centre Hospitalier Universitaire de Québec (CHU de Québec - Hôpital de l'Enfant-Jésus), Laval University, Québec, QC, Canada. Lynne.moore@fmed.ulaval.ca.
authors.forename: Lynne
authors.initials: L
authors.lastname: Moore
authors.affiliation: Department of social and preventive medicine, Laval University, Quebec, QC, Canada. brahim.cisse.1@ulaval.ca.|Population Health and Optimal Health Practices Research Unit, Trauma - Emergency - Critical Care Medicine, Centre de Recherche du Centre Hospitalier Universitaire de Québec (CHU de Québec - Hôpital de l'Enfant-Jésus), Laval University, Québec, QC, Canada. brahim.cisse.1@ulaval.ca.
authors.forename: Brahim
authors.initials: B
authors.lastname: Cisse
authors.affiliation: Department of social and preventive medicine, Laval University, Quebec, QC, Canada. brice-lionel.batomen-kuimi.1@ulaval.ca.|Population Health and Optimal Health Practices Research Unit, Trauma - Emergency - Critical Care Medicine, Centre de Recherche du Centre Hospitalier Universitaire de Québec (CHU de Québec - Hôpital de l'Enfant-Jésus), Laval University, Québec, QC, Canada. brice-lionel.batomen-kuimi.1@ulaval.ca.
authors.forename: Brice Lionel
authors.initials: BL
authors.lastname: Batomen Kuimi
authors.affiliation: Department of Critical Care Medicine, Medicine and Community Health Sciences, Institute for Public Health, University of Calgary, Calgary, AB, Canada. tstelfox@ucalgary.ca.
authors.forename: Henry T
authors.initials: HT
authors.lastname: Stelfox
authors.affiliation: Department of social and preventive medicine, Laval University, Quebec, QC, Canada. Alexis.Turgeon@fmed.ulaval.ca.|Population Health and Optimal Health Practices Research Unit, Trauma - Emergency - Critical Care Medicine, Centre de Recherche du Centre Hospitalier Universitaire de Québec (CHU de Québec - Hôpital de l'Enfant-Jésus), Laval University, Québec, QC, Canada. Alexis.Turgeon@fmed.ulaval.ca.|Department of Anesthesiology and Critical Care Medicine, Division of Critical Care Medicine, Laval University, Québec, QC, Canada. Alexis.Turgeon@fmed.ulaval.ca.
authors.forename: Alexis F
authors.initials: AF
authors.lastname: Turgeon
authors.affiliation: Population Health and Optimal Health Practices Research Unit, Trauma - Emergency - Critical Care Medicine, Centre de Recherche du Centre Hospitalier Universitaire de Québec (CHU de Québec - Hôpital de l'Enfant-Jésus), Laval University, Québec, QC, Canada. Francois.lauzier@med.ulaval.ca.|Department of Medicine, Laval University, Québec, QC, Canada. Francois.lauzier@med.ulaval.ca.
authors.forename: François
authors.initials: F
authors.lastname: Lauzier
authors.affiliation: Department of Surgery, Laval University, Québec, QC, Canada. Julienclement@hotmail.com.
authors.forename: Julien
authors.initials: J
authors.lastname: Clément
authors.affiliation: Institut National d'Excellence en Santé et en Services Sociaux, Montréal, Qc, Canada. Gilles.bourgeois@inesss.qc.ca.
authors.forename: Gilles
authors.initials: G
authors.lastname: Bourgeois
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002170:Canada; D003422:Critical Care; D005260:Female; D006295:Health Resources / Q000191:economics; D006301:Health Services Needs and Demand; D006760:Hospitalization; D006801:Humans; D007902:Length of Stay / Q000191:economics; D008297:Male; D008875:Middle Aged; D009656:North America; D012189:Retrospective Studies; D012923:Social Class; D014947:Wounds and Injuries; D055815:Young Adult