title: Venous thromboembolism as a marker of quality of care in trauma.
abstract: BACKGROUND
  Venous thromboembolism (VTE) is reported to occur among 7% to 58% of trauma patients. Variability in VTE rates might reflect differences in case mix and quality of care, but also screening practices or data capture. We explored the variation in VTE rates across trauma centers to determine its use as a measure of the quality of patient care.
  
  
  METHODS
  The National Trauma Data Bank (version 7.1, admission year 2006) was used to capture a cohort at risk for VTE. Crude and adjusted rates of VTE were determined, and the observed and expected rates were compared across centers. Outlier hospitals were defined as those with considerably more (or fewer) patients than expected. We then assessed the level of concordance between outlier status for deep vein thrombosis (DVT) and pulmonary embolism (PE). Intraclass correlation coefficients (ICC) were calculated to evaluate for the presence of a "center" effect using multilevel modeling.
  
  
  RESULTS
  The 22,421 patients met inclusion criteria from 30 trauma centers. There was marked variability in the rate of VTE across centers, ranging from 0.2% to 13.3%, which was more pronounced for DVT (0.2% to 13.1%) than for PE (0% to 1.7%). There was poor concordance for DVT and PE outlier status. Intraclass correlation coefficient was four times greater for DVT (0.23) than for PE (0.06).
  
  
  CONCLUSIONS
  There was substantial variation in rates of VTE across trauma centers. There was no relationship between DVT and PE outlier status, which is counter to the understanding of the biologic relationship between the two. Lastly, the very low Intraclass correlation coefficient for PE compared with DVT suggests that to a large extent, practice variation has very little impact on PE rates. In light of these findings and concerns about patient ascertainment of DVT, VTE rates might not be a useful measure of quality of care.
authors.affiliation: Trauma Program, Division of General Surgery, St Michael's Hospital, University of Toronto, Toronto, Canada.
authors.forename: Khumar
authors.initials: K
authors.lastname: Huseynova
authors.forename: Wei
authors.initials: W
authors.lastname: Xiong
authors.forename: Joel G
authors.initials: JG
authors.lastname: Ray
authors.forename: Najma
authors.initials: N
authors.lastname: Ahmed
authors.forename: Avery B
authors.initials: AB
authors.lastname: Nathens
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003953:Diagnosis-Related Groups; D004632:Emergency Medical Services / Q000592:standards; D005260:Female; D006801:Humans; D015601:Injury Severity Score; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D019984:Quality Indicators, Health Care; D012042:Registries; D012189:Retrospective Studies; D014193:Trauma Centers / Q000592:standards; D014481:United States / Q000453:epidemiology; D054556:Venous Thromboembolism / Q000453:epidemiology*; D014947:Wounds and Injuries / Q000453:epidemiology*; D055815:Young Adult