title: Understanding Hospital Volume-Outcome Relationship in Severe Traumatic Brain Injury.
abstract: The hospital volume-outcome relationship in severe traumatic brain injury (TBI) population remains unclear.
  
  
  
  To examine the relationship between volume of patients with severe TBI per hospital and in-hospital mortality, major complications, and mortality following a major complication (ie, failure to rescue).
  
  
  
  In a multicenter cohort study, data on 9255 adults with severe TBI were derived from 111 hospitals participating in the American College of Surgeons Trauma Quality Improvement Program over 2009-2011. Hospitals were ranked into quartiles based on their volume of severe TBI during the study period. Random-intercept multilevel models were used to examine the association between hospital quartile of severe TBI volume and in-hospital mortality, major complications, and mortality following a major complication after adjusting for patient and hospital characteristics. In sensitivity analyses, we examined these associations after excluding transferred cases.
  
  
  
  Overall mortality was 37.2% (n = 3447). Two thousand ninety-eight patients (22.7%) suffered from 1 or more major complication. Among patients with major complications, 27.8% (n = 583) died. Higher-volume hospitals were associated with lower mortality; the adjusted odds ratio of death was 0.50 (95% confidence interval: 0.29-0.85) in the highest volume quartile compared to the lowest. There was no significant association between hospital-volume quartile and the odds of a major complication or the odds of death following a major complication. After excluding transferred cases, similar results were found.
  
  
  
  High-volume hospitals might be associated with lower in-hospital mortality following severe TBI. However, this mortality reduction was not associated with lower risk of major complications or death following a major complication.
authors.affiliation: Sunnybrook Research Institute, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada.
authors.forename: Aziz S
authors.initials: AS
authors.lastname: Alali
authors.affiliation: Sunnybrook Research Institute, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Gomez
authors.affiliation: Sunnybrook Research Institute, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada.
authors.forename: Victoria
authors.initials: V
authors.lastname: McCredie
authors.affiliation: Division of Neurosurgery, Sunnybrook Health Sciences Center, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Todd G
authors.initials: TG
authors.lastname: Mainprize
authors.affiliation: Sunnybrook Research Institute, Sunnybrook Health Sciences Center, Toronto, Ontario, Canada.
authors.forename: Avery B
authors.initials: AB
authors.lastname: Nathens
mesh_terms: D000328:Adult; D000368:Aged; D000070642:Brain Injuries, Traumatic / Q000401:mortality / Q000601:surgery*; D015331:Cohort Studies; D005260:Female; D017052:Hospital Mortality; D006761:Hospitals / Q000592:standards*; D061847:Hospitals, High-Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D058996:Quality Improvement
keywords: Complications; Multilevel analysis; Quality improvement; Traumatic brain injury