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At least 19 recordsLinked to original sources

PubMed2003

Prediction of mortality in pediatric trauma patients: new injury severity score outperforms injury severity score in the severely injured.

BACKGROUND: The Injury Severity Score (ISS) is a widely accepted method of measuring severity of traumatic injury. A modification has been proposed--the New Injury Severity Score (NISS). This has been shown to predict mortality better in adult trauma patients, but it had no predictive benefit in pediatric patients. The aim of this study was to determine whether the NISS outperforms the ISS in a large pediatric trauma population. METHODS: Admissions in the National Pediatric Trauma Registry between April 1996 and September 1999 were included. The ISS and NISS were calculated for each patient. The study endpoints were mortality at hospital discharge, functional outcome in three domains (expression, locomotion, and feeding), and discharge disposition for the survivors. Predictive ability of each score was assessed by area under the receiver operating characteristic curve. RESULTS: The NISS and ISS performed equally well at predicting mortality in patients with lower injury severity (ISS < 25), but the NISS was significantly better at predicting mortality in the more severely injured patients. Both scores performed equally well at predicting expression and feeding ability. The NISS was superior to the ISS in predicting locomotion ability at discharge. Thirty-seven percent of patients had an NISS that was higher than their ISS. These patients had a significantly higher mortality and suffered worse functional outcomes. CONCLUSION: The NISS performs as well as the ISS in pediatric patients with lower injury severity and outperforms the ISS in those with higher injury severity.

Activities of Daily Living↗

PubMedDate not supplied

Injury Severity Score versus New Injury Severity Score for penetrating injuries.

INTRODUCTION: The New Injury Severity Score (NISS) was introduced in 1997 to improve outcome prediction based on anatomical severity scoring in trauma victims. Studies on populations of blunt trauma victims indicate that the NISS, predicts better than the Injury Severity Score (ISS) mortality post-injury, which is why the NISS has been recommended as the new "gold standard" for severity scoring. However, so far the accuracy of the NISS for penetrating injuries has not been validated against the ISS. METHODS: ISS and NISS scores were collected retrospectively for 1,787 war- and landmine victims in North Iraq. All victims only had penetrating injuries. The two tests were compared for prediction of short-term mortality and post-operative complications using Receiver Operating Characteristics (ROC) analysis. RESULTS: Both the ISS and the NISS predicted mortality with high accuracy (ROC area under curve 0.9). There were no significant differences between the two tests. The predictive accuracy for post-operative complications was moderate for both tests (ROC-AUC < 0.8), with the NISS performing significantly better than the ISS. CONCLUSION: The NISS does not perform better than the ISS in penetrating injuries. However, this study was done on a low-risk trauma population, thus the results should not be extrapolated to high severity trauma. Due to statistical shortcomings in studies previously published, studies on far larger cohorts are necessary before the NISS should be adopted as the new "gold standard" for severity scoring.

Explosions↗

PubMedDate not supplied

The relationships of skeletal injuries with trauma score, injury severity score, length of hospital stay, hospital charges, and mortality in children admitted to a regional pediatric trauma center.

Thirty-four-hundred and seventy-two children were consecutively admitted for acute traumatic injuries over a 34 month period to the Children's National Medical Center. The study comprised 805 patients who sustained 953 fractures and dislocations. The male to female ratio was 2:1. Age at the time of admission was evenly distributed over 16 years, with a mean of 8.3 years. Pedestrian accidents and falls each accounted for 34% of the musculoskeletal injuries, whereas motor vehicle accidents accounted for an additional 13%. The femur was the most commonly fractured bone, representing 22% of all fractures and dislocations, followed by the humerus (16%), tibia/fibula (12%), ankle/foot (13%), and radius/ulna (8%). Nine percent of the fractures were open. The average length of hospital stay was 8.6 days, and the average cost per hospital admission was $8,765. The mortality rate was 3%. Central musculoskeletal injuries (spine, clavicle/scapula, and pelvis) in our hospitalized patients were associated with the longest hospital stays and intensive care unit admissions, and lowest Trauma Scores, as well as the highest Injury Severity Scores, hospital charges, and mortality rates.

Accidents, Traffic↗

PubMed2004

Comparison of the New Injury Severity Score and the Injury Severity Score.

BACKGROUND: The New Injury Severity Score (NISS) was proposed in 1997 to replace the Injury Severity Score (ISS) because it is more sensitive for mortality. We aim to test whether this is true in our patients. METHODS: This study was a retrospective review of data from 6,231 consecutive patients over 3 years in the trauma registry of a Level I trauma center studying outcome, ISS, and NISS. RESULTS: Misclassification rates were 3.97% for the NISS and 4.35% for the ISS. The receiver operating characteristic curve areas were 0.936 and 0.94, respectively. Neither the ISS nor the NISS were well calibrated (Hosmer-Lemeshow statistic, 36.11 and 49.28, respectively; p < 0.001). CONCLUSION: The NISS should not replace the ISS, as they share similar accuracy and calibration.

Adolescent↗

PubMed2006

Childhood falls: characteristics, outcome, and comparison of the Injury Severity Score and New Injury Severity Score.

OBJECTIVES: The aim of this study was to determine the general characteristics of childhood falls, factors affecting on mortality, and to compare the Injury Severity Score (ISS) and the New Injury Severity Score (NISS) as predictors of mortality and length of hospital stay in childhood falls. METHODS: We retrospectively analysed over a period of 8 years children aged younger than14 years who had sustained falls and who were admitted to our emergency department. Data on the patients' age, sex, type of fall, height fallen, arrival type, type of injuries, scoring systems, and outcome were investigated retrospectively. The ISS and NISS were calculated for each patient. Comparisons between ISS and NISS for prediction of mortality were made by receiver operating characteristic (ROC) curve and Hosmer-Lemeshow (HL) goodness of fit statistics. RESULTS: In total, there were 2061 paediatric trauma patients. Falls comprised 36 (n = 749) of these admissions. There were 479 male and 270 female patients. The mean (SD) age was 5.01 (3.48) years, and height fallen was 3.8 (3) metres. Over half (56.6%) of patients were referred by other centres. The most common type of fall was from balconies (38.5%), and head trauma was the most common injury (50%). The overall mortality rate was 3.6%. The cut off value for both the ISS and NISS in predicting mortality was 22 (sensitivity 90.5%, specificity 95.4% for ISS; sensitivity 100%, specificity 88.7% for NISS) (p>0.05). Significant factors affecting mortality in logistic regression analysis were Glasgow Coma Scale (GCS) <9, ISS >22, and NISS >22. There were no significant differences in ROC between three scoring systems. The HL statistic showed poorer calibration (p = 0.02 v p = 0.37, respectively) of the NISS compared with the ISS. CONCLUSIONS: In our series, the head was the most frequent site of injury, and the most common type of fall was from balconies. Scores on the GCS, NISS, and ISS are significantly associated with mortality. The performance of the NISS and ISS in predicting mortality in childhood falls was similar.

Accidental Falls↗

PubMed2001

An overview of the injury severity score and the new injury severity score.

OBJECTIVE: The research was undertaken to describe the injury severity score (ISS) and the new injury severity score (NISS) and to illustrate their statistical properties. DESIGN: Descriptive analysis and assessment of the distribution of these scales. METHODS: Three data sources--the National Pediatric Trauma Registry; the Massachusetts Uniform Hospital Discharge Data Set; and a trauma registry from an urban level I trauma center in Massachusetts--were used to describe the distribution of the ISS and NISS among injured patients. RESULTS: The ISS/NISS was found to have a positively skewed distribution and transformation did not improve their skewness. CONCLUSION: The findings suggest that for statistical or analytical purposes the ISS/ NISS should not be considered a continuous variable, particularly if ISS/NISS is treated as a continuous variable for correlation with an outcome measure.

Adolescent↗

PubMed2005

The Injury Severity Score or the New Injury Severity Score for predicting intensive care unit admission and hospital length of stay?

OBJECTIVES: To compare the New Injury Severity Score (NISS) and the Injury Severity Score (ISS) as predictors of intensive care unit (ICU) admission and hospital length of stay (LOS) in an urban North American trauma population and in a subset of patients with head injuries. METHODS: The study population consisted of 23,909 patients from three urban level I trauma centres in the province of Quebec, Canada. The predictive accuracies of the NISS and the ISS were compared using Receiver Operator Characteristic (ROC) curves and Hosmer-Lemeshow (H-L) statistics for the logistic regression model of ICU admission and using r2 for the linear regression model of LOS. RESULTS: A total of 7660 (32%) patients were admitted to the ICU. Mean LOS was 8.2+/-2.5 days. In the whole sample, the NISS presented equivalent discrimination (area under ROC curve: NISS = 0.839 versus ISS = 0.843, p = 0.08) but better calibration (H-L statistic: 309 versus 611) for predicting ICU admission. In the subgroup patients with moderate to serious head injuries, the NISS was a better predictor of ICU admission in terms of both discrimination (area under ROC curve: NISS = 0.771 versus ISS = 0.747, p < 0.00001) and calibration (H-L statistic: 12 versus 21). The NISS explained more variation in LOS than the ISS for the whole sample (r2 = 0.254 versus 0.249, p = 0.0008) and in the sub-population with moderate to severe head injuries (r2 = 0.281 versus 0.263, p = 0.0002). CONCLUSIONS: The NISS is a better choice for case mix control in trauma research than the ISS for predicting ICU admission and LOS, particularly among patients with moderate to severe head injuries.

Adolescent↗

PubMed1999

The Pediatric Risk of Mortality (PRISM) Score and Injury Severity Score (ISS) for predicting resource utilization and outcome of intensive care in pediatric trauma.

OBJECTIVE: Mortality prediction in trauma is assessed using the Injury Severity Score (ISS) and Revised Trauma Score using Trauma Injury Severity Score (TRISS) methodology. The Pediatric Risk of Mortality (PRISM) score assesses mortality risk in critically ill children. We compared the ability of PRISM and ISS (using TRISS methodology) to predict resource utilization and outcome in pediatric trauma. DESIGN: Retrospective chart and database review. SETTING: Pediatric intensive care unit (PICU). PATIENTS: Consecutive admissions to a PICU over a 2-yr period. MEASUREMENTS AND MAIN RESULTS: Demographic data including PICU resource utilization and outcome were recorded. Data were recorded on 1,052 admissions (31 deaths), including 125 pediatric trauma patients (11 deaths). Patients were stratified into low- and high-risk categories based on PRISM and ISS scores. Patients with PRISM scores <6 and ISS scores <10 were classified as low risk. While both low-risk PRISM and ISS scores readily identified survivors, PRISM was the more sensitive indicator of resource utilization. PRISM, however, performed less well in determining risk-adjusted mortality as compared with ISS. CONCLUSION: PRISM readily stratifies pediatric trauma patients for resource utilization. PRISM appears to underestimate mortality in pediatric trauma as compared with ISS using TRISS methodology.

Bias↗

PubMed1991

[Trauma score and injury severity score in evaluation of the trauma patients: a preliminary report of 1000 cases].

It is important to evaluate trauma patients with a properly graded severity system in the emergency management of these patients. In this study the Trauma and the Injury Severity Scores based on the evaluation of trauma patients at the emergency services of Mackay Memorial Hospital and Taipei Medical College Hospital, and the mortality rate of these patients is analyzed. There was not a single mortality in patients with a Trauma Score of 15 or 16 and no survival in the patients with Trauma Scores under 11. Eighty-three of 1000 patients (8.3%) had a Trauma Score under 16, and hospitalization was necessary for most of them. All the 22 fatal cases had an Injury Severity Score greater than 24. The mortality rate was 70.6% for the patients with an Injury Severity Score greater than 30. This was the first trial in Taiwan to evaluate patients with the Trauma Score in the hope of aiding medical and paramedical staffs in the selection hospitals to which to transfer patients. All patients having a Trauma Score under 14 should be transferred to well-equipped trauma centers and those with a better score to other hospitals. The Injury Severity Score is nowadays used widely in the world to evaluate the severity and to predict the outcome of the patients. By comparing and utilizing these two grading systems, a more accurate evaluation of the trauma patients can be expected.

Emergency Medical Services↗

PubMed1992

Correlation between injury severity scores and subjective ratings of injury severity: a basis for trauma audit.

A retrospective review of 1900 road accident victims attending the emergency departments of two Melbourne hospitals was undertaken to identify Injury Severity Score levels which could distinguish between minor, moderate, severe and critical injury. Injuries scoring ISS 6 or below were designated 'minor' because they were associated with a low risk of requiring admission to hospital. Case notes of patients scoring above ISS 6 were then reviewed by a panel of clinicians, who independently rated each patient's overall injury severity as moderate, severe or critical according to what was recorded in the notes and their 'clinical' judgement. ISS values were compared with clinicians' ratings. Measures of each clinician's individual rating consistency, and correlation between pairs of clinicians with respect to inter-rater consistency, were made. By combining data from both hospitals it emerged that 'moderate' injury corresponded to ISS 8-13, 'severe' to ISS 14-20 and 'critical' to ISS 21 and above. These ISS breakpoints will be useful in selecting groups of injured patients for future trauma audit studies.

Accidents, Traffic↗

PubMed2003

Correlation of revised trauma score and injury severity score (TRISS) predicted probability of survival with peer-reviewed determination of trauma deaths.

Trauma deaths at our institution are evaluated by a multidisciplinary trauma committee. The purpose of this study was to evaluate preventable trauma deaths (PRDs) as determined by our review committee and correlate them with the Revised Trauma Score and Injury Severity Score (TRISS) probability of survival (PS). A total of 10,002 patients were identified. The PS was calculated using the TRISS method. The Z scores were calculated and the predicted number of deaths was established. The actual number of deaths was compared with the predicted number of deaths. PRDs were compared with the actual and predicted deaths. The Z score was 0.79, which meant we observed more deaths than predicted by TRISS. We had 281 deaths compared with 271 deaths predicted by TRISS. Peer review characterized 45 deaths as preventable. Although we performed well when our outcomes were compared with TRISS predicted outcomes our PRD rate was higher. The higher the PS the more likely the death was found preventable by peer review. We conclude that for our patient population the peer review process is very sensitive and may be more discerning in identifying PRD than TRISS.

Hospital Mortality↗

PubMed1995

Use of the Injury Severity Score in head injury.

As part of a study of the early management of severe head injury, the use of the Glasgow Coma Score (GCS), Injury Severity Score (ISS) and TRISS was investigated. These injury scores were compared in correlating with outcome at one year as assessed by the Glasgow Outcome Score (GOS) and mortality. One hundred and thirty-one patients had a severe head injury, as defined by an ISS of 16 or higher, in whom the Abbreviated Injury Score (AIS) for craniocerebral injury was 3 or higher. Seventy-eight of these also fulfilled the accepted GCS definition of severe head injury (GCS less than 8 with no eye-opening). Thirty-eight had evacuation of an acute intracranial haematoma; 26 of these patients would not have been classified as severe head injury by GCS. The overall mortality rate was 38 per cent, and 24 per cent for those transferred to the neurosurgical unit. TRISS was slightly better than GCS for predicting outcome based on both GOS and mortality, however this difference was not significant. TRISS identified patients who died that are not considered as severe head injury by GCS. Use of TRISS allows the effects of systemic factors and other injuries to be taken into account when assessing severity of head injury.

Craniocerebral Trauma↗

PubMed1993

Comparison of APACHE II, Trauma Score, and Injury Severity Score as predictors of outcome in critically injured trauma patients.

Trauma Score (TS), APACHE II score, and Injury Severity Score (ISS) have been utilized to quantitate severity of illness in various groups of patients. The purpose of this study was to compare the relationship of the APACHE II score, TS, and "computer-derived" ISS with outcome in critically injured trauma patients. Data were recorded prospectively in a computer database for 428 consecutive trauma admissions. Stepwise discriminate analysis was utilized to determine the best predictor of both intensive care unit (ICU) and hospital outcome. Forty-two patients died in the ICU (10%), and another 18 patients died after leaving the ICU (4%), for a total mortality rate of 14%. The mean p value and partial R2 value obtained from stepwise discriminant analysis of the relationships between APACHE II score, TS, and ISS to ICU and hospital survival are shown. APACHE II score was the best predictor of both ICU and hospital outcome in these critically ill trauma patients. However, when combining all three measures (APACHE II score, TS, and ISS), only a portion of the variance in outcome is explained by the scores (R2 < 0.05). We conclude that scoring systems for outcome prediction should be utilized only as an adjunct to clinical assessment in the evaluation of the severity of illness and mortality risk in critically ill trauma patients.

Female↗

PubMed1998

The end of the Injury Severity Score (ISS) and the Trauma and Injury Severity Score (TRISS): ICISS, an International Classification of Diseases, ninth revision-based prediction tool, outperforms both ISS and TRISS as predictors of trauma patient survival, hospital charges, and hospital length of stay.

INTRODUCTION: Since their inception, the Injury Severity Score (ISS) and the Trauma and Injury Severity Score (TRISS) have been suggested as measures of the quality of trauma care. In concept, they are designed to accurately assess injury severity and predict expected outcomes. ICISS, an injury severity methodology based on International Classification of Diseases, Ninth Revision, codes, has been demonstrated to be superior to ISS and TRISS. The purpose of the present study was to compare the ability of TRISS to ICISS as predictors of survival and other outcomes of injury (hospital length of stay and hospital charges). It was our hypothesis that ICISS would outperform ISS and TRISS in each of these outcome predictions. METHODS: "Training" data for creation of ICISS predictions were obtained from a state hospital discharge data base. "Test" data were obtained from a state trauma registry. ISS, TRISS, and ICISS were compared as predictors of patient survival. They were also compared as indicators of resource utilization by assessing their ability to predict patient hospital length of stay and hospital charges. Finally, a neural network was trained on the ICISS values and applied to the test data set in an effort to further improve predictive power. The techniques were compared by comparing each patient's outcome as predicted by the model to the actual outcome. RESULTS: Seven thousand seven hundred five patients had complete data available for analysis. The ICISS was far more likely than ISS or TRISS to accurately predict every measure of outcome of injured patients tested, and the neural network further improved predictive power. CONCLUSION: In addition to predicting mortality, quality tools that can accurately predict resource utilization are necessary for effective trauma center quality-improvement programs. ICISS-derived predictions of survival, hospital charges, and hospital length of stay consistently outperformed those of ISS and TRISS. The neural network-augmented ICISS was even better. This and previous studies demonstrate that TRISS is a limited technique in predicting survival resource utilization. Because of the limitations of TRISS, it should be superseded by ICISS.

Adult↗

PubMed1998

Lethal abdominal gunshot wounds at a level I trauma center: analysis of TRISS (Revised Trauma Score and Injury Severity Score) fallouts.

BACKGROUND: The TRISS methodology (composite index of the Revised Trauma Score and the Injury Severity Score) has become widely used by trauma centers to assess quality of care. The American College of Surgeons recommends including negative TRISS fallouts (fatally injured patients predicted to survive by the TRISS methodology) as a filter to select patients for peer review. The purpose of this study was to analyze the TRISS fallouts among patients with lethal abdominal gunshot wounds admitted to a level I trauma center. STUDY DESIGN: All patients categorized as TRISS fallouts admitted from January 1995 through December 1996 were analyzed. RESULTS: During the study period, 848 patients with abdominal gunshot wounds were admitted. Of the 108 patients with any sign of life on admission who subsequently died, 39 (36%) were TRISS fallouts. The patients were largely young (mean age, 29 years) and male (87%), received rapid transport (mean scene time, 11 minutes), and had an attending-led trauma-team response (<5 minutes, 87%). Major vascular (80%) and multiple intraabdominal injuries (90%) predominated. The mean Penetrating Abdominal Trauma Index was 40.3. The mean TRISS probability of survival was 89%. The peer-review process deemed the deaths to be nonpreventable in 38 patients (97%) and potentially preventable in one patient (3%). CONCLUSIONS: "TRISS fallouts" were predominantly patients who died despite receiving rapid prehospital transport, rapid senior-level trauma-team response, and surgical intervention for a serious complex of injuries. We conclude that without regional adjustment of coefficients used to predict the probability of survival, the TRISS methodology is of limited use in patients with abdominal gunshot wounds.

Abdominal Injuries↗

PubMed1992

Injury severity score, head injury, and patient wait days: contributions to extended trauma patient length of stay.

The ability of level I trauma units to operate efficiently may be hampered by the presence of a number of patients with an excessive length of stay (LOS). In an attempt to determine causes for and suggest potential solutions to the long-term occupation of beds in an acute care trauma facility, the cases of patients with extended LOSs in a level I trauma unit were examined. Study patients were survivors admitted between January 1, 1986, and December 31, 1989. Patients with a LOS greater than one standard deviation above the mean (n = 221) were assigned to the Long LOS group, and the remaining 1250 patients to the Short LOS group. Long and Short LOS patient groups were compared on a number of variables including injury Severity Score, number of body systems injured, surgical procedures required, blood products used, AIS scores per body region, and patient wait days. Both an increased severity of injury and a lack of available chronic and rehabilitation beds for the head-injured patients contributed to excessive patient LOS in this acute care setting. Additional rehabilitation and chronic care beds are required to free acute care beds for the efficient operation of a level I trauma unit.

Craniocerebral Trauma↗

PubMed2002

Predictors of mortality in adult trauma patients: the physiologic trauma score is equivalent to the Trauma and Injury Severity Score.

BACKGROUND: Several statistical models (Trauma and Injury Severity Score [TRISS], New Injury Severity Score [NISS], and the International Classification of Disease, Ninth Revision-based Injury Severity Score [ICISS]) have been developed over the recent decades in an attempt to accurately predict outcomes in trauma patients. The anatomic portion of these models makes them difficult to use when performing a rapid initial trauma assessment. We sought to determine if a Physiologic Trauma Score, using the systemic inflammatory response syndrome (SIRS) score in combination with other commonly used indices, could accurately predict mortality in trauma. STUDY DESIGN: Prospective data were analyzed in 9,539 trauma patients evaluated at a Level I Trauma Center over a 30-month period (January 1997 to July 1999). A SIRS score (1 to 4) was calculated on admission (1 point for each: temperature > 38 degrees C or < 36 degrees C, heart rate > 90 beats per minute, respiratory rate > 20 breaths per minute, neutrophil count > 12,000 or < 4,000. SIRS score, Injury Severity Score (ISS), Revised Trauma Score (RTS), TRISS, Glasgow Coma Score, age, gender, and race were used in logistic regression models to predict trauma patients' risk of death. The area under the receiver-operating characteristic curves of sensitivity versus 1-specificity was used to assess the predictive ability of the models. RESULTS: The study cohort of 9,539 trauma patients (of which 7,602 patients had complete data for trauma score calculations) had a mean ISS of 9 +/- 9 (SD) and mean age of 37 +/- 17 years. SIRS (SIRS score > or = 2) was present in 2,165 of 7,602 patients (28.5%). In single-variable models, TRISS and ISS were most predictive of outcomes. A multiple-variable model, Physiologic Trauma Score combining SIRS score with Glasgow Coma Score and age (Hosmer-Lemenshow chi-square = 4.74) was similar to TRISS and superior to ISS in predicting mortality. The addition of ISS to this model did not significantly improve its predictive ability. CONCLUSIONS: A new statistical model (Physiologic Trauma Score), including only physiologic variables (admission SIRS score combined with Glasgow Coma Score and age) and easily calculated at the patient bedside, accurately predicts mortality in trauma patients. The predictive ability of this model is comparable to other complex models that use both anatomic and physiologic data (TRISS, ISS, and ICISS).

Adult↗

PubMed1996

ICISS: an international classification of disease-9 based injury severity score.

BACKGROUND: The Injury Severity Score (ISS) has served as the standard summary measure of human trauma for 20 years. Despite its stalwart service, the ISS has two weaknesses: it relies upon the consensus derived severity estimates for each Abbreviated Injury Scale (AIS) injury and considers, at most, only three of an individual patient's injuries, three injuries that often are not even the patient's most severe injuries. Additionally, the ISS requires that all patients have their injuries described in the AIS lexicon, an expensive step that is currently taken only at hospitals with a zealous commitment to trauma care. We hypothesized that a data driven alternative to ISS that used empirically derived injury severities and considered all of an individual patient's injuries would more accurately predict survival. METHODS: Survival risk ratios were derived for every International Classification of Disease 9th Edition (ICD-9) injury category (800-959.9) using the North Carolina State Discharge Database experience with 300,000 trauma patients over 5 years. An ICD-9 Injury Severity Score (ICISS) was then defined as the product of all survival risk ratios for an individual patient's traumatic ICD-9 codes. We compared the performance of ISS and ICISS in a group of 3,142 patients accrued at the University of New Mexico Trauma Center over 4 years. These patients had both AIS and ICD-9 descriptors meticulously assigned prospectively by designated trauma data base personnel. RESULTS: ICISS outperformed ISS at a level that was highly statistically significant (p < 0.0001) and may be clinically important: ISS misclassification rate 7.67%, ISS Receiver Operator Characteristic Curve area = 0.872; ICISS misclassification rate 5.95%, ICISS Receiver Operator Characteristic Curve area = 0.921. Moreover, these improvements are largely preserved when ICISS is used in a probability of survival model that includes age, mechanism, and revised trauma score. About half of ICISS's improvement in predictive power is because of its use of an individual patient's worst three injuries regardless of body region. The remainder is because of better modeling of individual injuries and allowing all injuries to contribute to the final score. CONCLUSIONS: We conclude that ICISS is a much better predictor of survival than ISS in injured patients. The use of the ICD-9 lexicon may avoid the need for AIS coding, and thus may add an economic incentive to the statistical appeal of ICISS. It is possible that a similar data driven revision of ISS using the AIS vocabulary might perform as well or better than ICISS. Indeed, the actual lexicon used to divide up the injury "landscape" into individual injuries may be of little consequence so long as all injuries are considered and empirically derived SRRs are used to calculate the final injury measure.

Disease↗