Advertisement

Validating the Injury Severity Score (ISS) in Different Populations: ISS Predicts Mortality Better Among Hispanics and Females

      Introduction

      The Injury Severity Score (ISS) is the most commonly used measure of injury severity. The score has been shown to have excellent predictive capability for trauma mortality and has been validated in multiple data sets. However, the score has never been tested to see if its discriminatory ability is affected by differences in race and gender.

      Objective

      This study is aimed at validating the ISS in men and women and in three different race/ethnic groups using a nationwide database.

      Methods

      Retrospective analysis of patients age 18–64 y in the National Trauma Data Bank 7.0 with blunt trauma was performed. ISS was categorized as mild (<9,) moderate (9–15), severe (16–25), and profound (>25). Logistic regression was done to measure the relative odds of mortality associated with a change in ISS categories. The discriminatory ability was compared using the receiver operating characteristics curves (ROC). A P value testing the equality of the ROC curves was calculated. Age stratified analyses were also conducted.

      Results

      A total of 872,102 patients had complete data for the analysis on ethnicity, while 763,549 patients were included in the gender analysis. The overall mortality rate was 3.7%. ROC in Whites was 0.8617, in Blacks 0.8586, and in Hispanics 0.8869. Hispanics have a statistically significant higher ROC (P value < 0.001). Similar results were observed within each age category. ROC curves were also significantly higher in females than in males.

      Conclusion

      The ISS possesses excellent discriminatory ability in all populations as indicated by the high ROCs.

      Key Words

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'

      Subscribe:

      Subscribe to Journal of Surgical Research
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect

      References

      1. Center for Disease Control and Prevention (CDC) Injury control homepage. http://www.cdc.gov/injury/Images/accessed December 3, 2009.

      2. Center for disease control wisqars Webpage. http://www.cdc.gov/injury assessed Jan 6, 2009.

        • Baker S.P.
        • O'Neill B.
        • Haddon Jr., W.
        • et al.
        The Injury Severity Score: A method for describing patients with multiple injuries and evaluating emergency care.
        J Trauma. 1974; 14: 187
        • Baker S.P.
        • O'Neill B.
        The Injury Severity Score: An update.
        J Trauma. 1976; 16: 882
        • Linn S.
        The injury severity score- importance and uses.
        Ann Epidemiol. 1995; 5: 440
      3. Injury Severity Scoring www.surgicalcriticalcare.net/Resources/injury_severity _scoring.pdf. Accessed November 8, 2009.

        • Stevenson M.
        • Segui-Gomez M.
        • Lescohier I.
        • et al.
        An overview of the injury severity score and the new injury severity score.
        Inj Prev. 2001; 7: 10
        • Champion H.R.
        • Copes W.S.
        • Sacco W.J.
        • et al.
        A new characterization of injury severity.
        Trauma. 1990; 30 (discussion 545): 539
        • Meredith J.W.
        • Evans G.
        • Kilgo P.D.
        • et al.
        A comparison of the abilities of nine scoring algorithms in predicting mortality.
        Trauma. 2002; 53 (discussion 628): 621
        • Sacco W.J.
        • Mackenzie E.J.
        • Champion H.R.
        • et al.
        Comparison of alternative methods for assessing injury severity based on anatomic descriptors.
        J Trauma. 1999; 47: 441
        • Glance L.G.
        • Turner M.
        • et al.
        Expert consensus versus empirical estimation of injury severity; effect on quality measurement in trauma.
        Arch Surg. 2009; 144: 326
        • Hannan E.L.
        • Waller C.H.
        • et al.
        A comparison among the abilities of various injury severity measures to predict mortality with and without accompanying physiologic information.
        J Trauma. 2005; 58: 244
        • Bamber D.
        The area above the ordinal dominance graph and the area below the receiver operating characteristic graph.
        J Mathemat Psychol. 1975; 12: 387
        • DeLong E.R.
        • DeLong D.M.
        • Clarke-Pearson D.L.
        Comparing the areas under two or more correlated receiver operating characteristic curves: A nonparametric approach.
        Biometrics. 1988; 44: 837
        • Hanley J.A.
        • McNeil B.J.
        The meaning and use of the area under a receiver operating characteristic (ROC) curve.
        Radiology. 1982; 143: 29
      4. Stata FAQ. UCLA: Academic Technology Services, Statistical Consulting Group. from http://www.ats.ucla.edu/stat/stata/faq/roc.htm. Accessed November 7, 2009.

      5. Interpreting diagnostic tests [homepage]. Available at: http://gim.unmc.edu/dxtests/roc3.htm. Accessed November 5, 2009.

        • StataCorp
        Stata Statistical Software: Release 10.
        StataCorp LP, CollegeStation, TX2007
        • Haider A.H.
        • Crompton J.G.
        • Oyetunji T.
        • et al.
        Females have fewer complications and lower mortality following trauma than similarly injured males: A risk adjusted analysis of adults in the National Trauma Data Bank.
        Surgery. 2009; 146: 308
        • Mullins R.J.
        • Veum-Stone J.
        • Hedges J.R.
        • et al.
        An analysis of hospital discharge index as a trauma data base.
        J Trauma. 1995; 39: 941
        • Brotman S.
        • McMinn D.L.
        • Copes W.S.
        • et al.
        Should survivors with an injury severity score less than 10 be entered in a statewide trauma registry?.
        J Trauma. 1991; 31: 1233
        • Brenneman F.D.
        • Boulanger B.R.
        • McLellan B.A.
        • et al.
        Acute and long-term outcomes of extremely injured blunt trauma victims.
        J Trauma. 1995; 39: 320
        • Osberg J.S.
        • DiScala C.
        Morbidity among pediatric motor vehicle crash victims: The effectiveness of seat belts.
        Am J Public Health. 1992; 82: 422
        • Burns C.M.
        The 1990 Fraser Gurd lecture: A Canadian trauma registry system—nine years experience.
        J Trauma. 1991; 31: 854
        • Nelson D.E.
        • Peterson T.D.
        • Chorba T.L.
        • et al.
        Cost savings associated with increased safety belt use in Iowa, 1987–1988.
        Accid Anal Prev. 1993; 25: 521
        • Husum H.
        • Strada G.
        Injury Severity Score versus New Injury Severity Score for Penetrating Injuries.
        Prehosp Disaster Medicine. 2002; 17: 27
        • Haider A.H.
        • Chang D.C.
        • Efron D.
        • et al.
        Race and insurance status as risk factors for trauma mortality.
        Arch Surg. 2008; 143: 945
        • George R.L.
        • McGwin G.
        • et al.
        The association between gender and mortality among trauma patients as modified by age.
        J Trauma. 2003; 54: 464