title: The attributable mortality and length of stay of trauma-related complications: a matched cohort study.
abstract: OBJECTIVE
  To determine the attributable mortality (AM) and excess length of stay because of complications or complication groupings in the National Trauma Data Bank.
  
  
  BACKGROUND
  Resources devoted to performance improvement activities should focus on complications that significantly impact mortality and length of stay. To determine which post-traumatic complications impact these outcomes, we conducted a matched cohort study. AM is the proportion of all deaths that can be prevented if the complication did not occur.
  
  
  METHODS
  We identified severely injured patients (Injury Severity Score, > or =9) at centers that contribute complications to the National Trauma Data Bank. To estimate the AM, a patient with a specific complication was matched to 5 patients without the complication. Matching was based on demographics and injury characteristics. Residual confounding was addressed through a logistic regression model. To estimate excess length of stay, matching covariates were identified through a Poisson regression model. Each case was required to match the control on all variables, and one control was selected per case.
  
  
  RESULTS
  Of the 94,795 patients who met the inclusion criteria, 3153 died. The overall mortality rate was 3.33%, and 10,478 (11.1%) patients developed at least 1 complication. Four complication groupings (cardiovascular, acute respiratory distress syndrome, renal failure, and sepsis) were associated with significant AM. Infectious complications (surgical infections, sepsis, and pneumonia) were associated with the greatest excess length of stay.
  
  
  CONCLUSIONS
  This study used AM and excess length of stay to identify trauma-related complications for external benchmarking. Guideline development and performance improvement activities need to be focused on these complications to significantly reduce the probability of poor outcomes following injury.
authors.affiliation: American College of Surgeons, Division of Research and Optimal Patient Care, Chicago, IL, USA. aingraham@facs.org
authors.forename: Angela M
authors.initials: AM
authors.lastname: Ingraham
authors.forename: Wei
authors.initials: W
authors.lastname: Xiong
authors.forename: Mark R
authors.initials: MR
authors.lastname: Hemmila
authors.forename: Shahid
authors.initials: S
authors.lastname: Shafi
authors.forename: Sandra
authors.initials: S
authors.lastname: Goble
authors.forename: Melanie L
authors.initials: ML
authors.lastname: Neal
authors.forename: Avery B
authors.initials: AB
authors.lastname: Nathens
mesh_terms: D000328:Adult; D000368:Aged; D019985:Benchmarking; D016009:Chi-Square Distribution; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D015601:Injury Severity Score; D007902:Length of Stay / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D016012:Poisson Distribution; D011183:Postoperative Complications / Q000401:mortality*; D012042:Registries; D012307:Risk Factors; D018709:Statistics, Nonparametric; D014481:United States / Q000453:epidemiology; D014947:Wounds and Injuries / Q000401:mortality* / Q000601:surgery*