Biomedical subjects

Eric Bergeron

Publications and source records attributed to Eric Bergeron.

At least 19 recordsLinked to original sources

PubMed2006

Statistical validation of the Glasgow Coma Score.

BACKGROUND: To validate the predictive value of the Glasgow Coma Score (GCS) and find the best way to model the score in a logistic regression model predicting mortality. METHODS: Analyses were based on 20,494 patients from the trauma registries of three urban Level I trauma centers in the province of Quebec, Canada. The predictive value of the GCS and its components was evaluated in logistic regression models predicting in-hospital mortality with measures of discrimination and calibration. The performance of the GCS with no transformation and as an ordered categorical variable was compared with two transformation techniques: fractional polynomials and spline regression. RESULTS: The GCS had excellent discrimination (area under Receiving Operator Characteristic Curve=0.833 95% confidence interval=0.820-0.846) but fairly poor calibration (Pearson's Chi-squared statistic=122 on 11 df). The eye component added no predictive information to the verbal and motor components in the whole sample but was important in certain sub-populations. Using the three components separately, rather than the sum, did not improve the predictive model. Fractional polynomial transformation of the GCS improved calibration and spline regression performed even better. GCS modeled as an ordered categorical variable performed badly both in terms of discrimination and calibration. CONCLUSIONS: The GCS in its present form is an efficient predictor of in-hospital mortality, which could benefit from statistical transformation in logistic regression models when the accuracy of estimated probabilities of mortality is important. The common use of GCS categories for modeling mortality leads to loss of information and should be discarded.

Aged↗

PubMed2006

Paying the price of excluding patients from a trauma registry.

BACKGROUND: The goal of this study was to evaluate the impact of different trauma registry exclusion criteria on the assessment of trauma populations and outcome. METHODS: All patients admitted to a Canadian regional trauma center from April 1, 1993 to March 31, 2002 with a diagnosis of trauma (ICD-9 codes 800 to 959) were reviewed. TOTAL included everyone. REGISTRY included only patients meeting any of four criteria: death during hospital stay, transfer received from another hospital, admission to the intensive care unit, or hospital stay of 3 days or more. NOHIP excluded patients with isolated hip fracture. REG/NOHIP combined both. ISS12 and ISS15 excluded patients with ISS <12 and 15, respectively. RESULTS: There were 6,839 trauma patients. The percentage of excluded patients by group was: REGISTRY, 21.2%; NOHIP, 14.7%; REG/NOHIP, 34.9%; ISS12, 75%; and ISS15, 80.3%. Median length of stay was 7 days. Exclusions represented a total number of hospitalization days varying from 1.9% to 65.5% of TOTAL. Mortality was 6.9% for TOTAL, 8.6% for REGISTRY (p < 0.001), 5.7% for NOHIP (p = 0.009), 7.5% for REG/NOHIP (p=NS), 16.1% for ISS12 (p < 0.001), and 20.4% for ISS15 (p < 0.001). In groups with exclusions, transfer to long-term care varied from 0.14% to 23.5% in the excluded patients. For rehabilitation, these percentages varied from 0.14% to 17.6%. CONCLUSIONS: Registry exclusion criteria significantly alter the apparent severity of injury and resource utilization. The use of divergent exclusion criteria in the analysis of trauma registry data may be misleading.

Adult↗

PubMed2006

A simple fall in the elderly: not so simple.

BACKGROUND: The goal of this study was to evaluate the burden of falls in the elderly in a Canadian tertiary trauma center. METHODS: Patients admitted to Charles-LeMoyne Hospital with a low velocity fall (LVF) from April 1, 1993 to March 31, 2000 were individually reviewed. Elderly was defined as age 65 years and older. A region was considered to be injured if Abbreviated Injury Scale was greater than or equal to 2. RESULTS: There were 2,333 patients with LVF, 41.4% of all blunt trauma admissions. Median Injury Severity Score was 9 for elderly compared with 5 for young (p < 0.001). Injuries were significantly more frequent to head, face, thorax, and lower limbs in the elderly. Mortality (13.4% versus 0.9%; p < 0.001), length of stay (median = 15 versus 3 days; p < 0.001) and long-term care facility reference (19.3% versus 1.1%, p < 0.001) were significantly higher in the elderly. CONCLUSIONS: LVF is a frequent cause of admission for trauma in the elderly. Despite the apparent benign nature of the mechanism, LVF is associated with more severe injuries and worse outcome.

Abbreviated Injury Scale↗

PubMed2006

Unification of the revised trauma score.

BACKGROUND: The Revised Trauma Score (RTS) calculated with Major Outcome Trauma Study weights (MTOS-RTS) is currently the standard physiologic severity score in trauma research and quality control. It is often confused with the Triage-RTS (T-RTS), a version that is easier to calculate but only intended for clinical triage. OBJECTIVES: To compare the accuracy of the MTOS-RTS to the RTS calculated with weights derived from the study population (POP-RTS) and the T-RTS, for predicting mortality in a trauma population. METHODS: The study population consists of 22,388 patients, drawn from the trauma registries of three Level I trauma centers. The predictive accuracy of the MTOS-RTS, POP-RTS, and the T-RTS were compared using measures of discrimination and model fit from logistic regression models. RESULTS: The MTOS-RTS, the POP-RTS, and the T-RTS had the same discrimination (Area under the Receiver Operating Curve [AUC] = 0.841). The POP-RTS and the T-RTS had a slightly better model fit than the MTOS-RTS (AIC = 8010, 8010, and 8067, respectively). The T-RTS had equal discrimination and equal or better model fit than the MTOS-RTS in the whole sample, in each of the three trauma centers and in the population of patients with severe head trauma. The T-RTS was also equivalent to the POP-RTS in all of these population sub-groups. CONCLUSIONS: The T-RTS could replace the MTOS-RTS as the standard physiologic severity score for trauma outcome prediction. The advantages of using the T-RTS over the MTOS-RTS are ease of calculation, the need for only one measure for triage and mortality prediction purposes and universal adaptation to a broad range of trauma populations.

Aged↗

PubMed2006

Two worst injuries in different body regions are associated with higher mortality than two worst injuries in the same body region.

BACKGROUND: The Injury Severity Score (ISS) accounts for only one injury in each body region. The New Injury Severity Score (NISS) considers all injuries in a body region. Despite a big difference between the two scores in patients with multiple injuries, the NISS does not offer significant improvement in mortality prediction. This paper hypothesizes that two injuries in different body regions are associated with higher mortality than two injuries in the same body region, independently of injury severity. METHODS: The population consisted of 15,200 patients with two or more injuries from the Quebec Trauma Registry, Canada, abstracted between 1998 and 2004. The two worst injuries were considered. Logistic regression analysis was used to assess the mortality odds ratio of having two worst injuries in different body regions (DR) compared with two worst injuries in the same body region (SR), while adjusting for the severity and the body region of the two worst injuries and age. RESULTS: A total of 5,869 patients (49%) had their worst injuries in DR. DR patients had 75% higher risk of mortality than SR patients (odds ratio = 1.75, 95% confidence interval = 1.42-2.15). CONCLUSION: After accounting for differing injury severity, patients with their two worst injuries in different body regions have higher mortality than those with their two worst injuries in the same region. Results suggest that the observed effect is not due to a foible in the Abbreviated Injury Scale system but rather to physiologic, clinical, or organizational elements. The results of this study should be considered in the development of future injury severity instruments and may have implications for the care of patients with multiple injuries.

Aged↗

PubMed2006

Statistical validation of the Revised Trauma Score.

BACKGROUND: To validate the accuracy of the Revised Trauma Score (RTS) and its components for predicting in-hospital mortality. METHODS: Analyses were based on 22,388 patients from the trauma registries of three urban Level I trauma centers in the province of Quebec, Canada. The accuracy of RTS coded variables for the Glasgow Coma Score (GCSc), Systolic Blood Pressure (SBPc), and Respiratory Rate (RRc) for predicting mortality was evaluated in logistic regression models with measures of discrimination and model fit and compared with Fractional Polynomial (FP) transformations of each component. RESULTS: RTS coded variables were associated with sparse data distributions and did not accurately represent the relation of GCS, SBP, and RR to mortality. FP models were always associated with significantly better discrimination (all p < 0.00001) and model fit. Survival probability estimates generated by the model with FP transformations were significantly different to those generated by the model with RTS-coded variables. CONCLUSIONS: The RTS in its present form does not accurately describe the relation of GCS, SBP, and RR to mortality. FP transformation would improve the accuracy of predicted survival probabilities used for performance evaluation and may improve control of confounding caused by of physiologic severity case mix in trauma research.

Adolescent↗

PubMed2006

To close or not to close, that is one of the questions? Perceptions of Trauma Association of Canada surgical members on the management of the open abdomen.

BACKGROUND: The optimal abdominal closure in critically ill surgical/trauma patients remains controversial with a wide variety of commonly employed techniques. We sought to evaluate clinical equipoise by surveying Canadian surgeons regarding the use of temporary abdominal closure strategies in damage control and emergency situations. METHODS: A structured mixed-mode (Website and paper), scenario-based questionnaire was developed by members of the Canadian Trauma Trials Collaborative and directed to surgical members of the Trauma Association of Canada (TAC). RESULTS: The overall response rate was 84% (86 out of 102). In resuscitated hemodynamically stable trauma patients, 42% (29 out of 69) of respondents elected to primarily close an "extremely tight" abdominal cavity while only 23% (16 out of 70) would primarily close the same patient when physiologic exhaustion (Damage control (DC) conditions-hypothermia, acidosis, and coagulopathy) supervened. Although the majority reported preference for temporizing abdominal closures [73% (51 out of 70) non-DC, 75% (52 out of 69) DC] when the fascia was physically impossible to close; the reported primary use of mesh in these situations was quite high [24.6% (17 out of 69) non-DC, 24% (16 out of 69) DC], including a reported 7% (5 out of 69) nonabsorbable mesh usage in a contaminated octogenarian abdomen. CONCLUSION: Reported opinions suggest an overall appreciation for markers of "Damage Control," although clinical equipoise exists regarding the preferred technique and a frequent early use of mesh. These results highlight the necessity for further research but suggest challenges in defining a common standard for multicenter trials.

Abdomen↗

PubMed2006

Spill your guts! Perceptions of Trauma Association of Canada member surgeons regarding the open abdomen and the abdominal compartment syndrome.

BACKGROUND: To survey surgeon opinion regarding the management of the open abdomen (OA) and abdominal compartment syndrome (ACS) to assess current practice and direct future prospective clinical studies. METHODS: Opinions of self-designated trauma, general, pediatric, and vascular surgeons belonging to the Trauma Association of Canada (TAC), were surveyed through a mixed-mode (mail and Web based) questionnaire. RESULTS: Among 102 eligible candidates, 86 (84%) responded; 83% did regular trauma call, 45% regular critical care call being a separate call 79% of the time; 79% worked in centers serving >500,000 people; the median year of practice entry was 1997. There was no standard definition of what constituted an "open abdomen", preferred time for re-operation, or preferred method for alternate fascial closure, although 90% reported having not closing the fascia after a trauma laparotomy. Being "physically unable" was reported as an indication twice as often as objective measures of airway or bladder pressures. The decision to proceed with OA was reported as rarely or never being made preoperatively by 78% of respondents. None reported an institutional policy regarding OA. Eighty-four percent reported (re)opening an abdomen for primary ACS, 46% for secondary ACS, 28% for tertiary ACS. Self-assessed familiarity for the ACS was 6/7 on a Likert scale. Physical examination was reported as a diagnostic criterion for ACS by 66%, and used to screen by 21% of respondents. CONCLUSIONS: There is no consensus regarding definition, functional indications, or management of an open abdomen in the perceptions of Canadian trauma providers despite a high self reported level of familiarity with the abdominal compartment syndrome. This is an area of practice with potential and requirements for further multi-center study.

Abdomen↗

PubMed2006

Is the delay to surgery for isolated hip fracture predictive of outcome in efficient systems?

BACKGROUND: Adverse outcomes for patients with isolated hip fracture have been documented when preoperative delay is longer than 48 hours. An efficient system will have the capacity to repair all hip fractures within 48 hours. We hypothesized that in an efficient system, there would be a medical justification for a delay greater than 48 hours. The purpose of this study was to identify the causes and outcome of delay for hip surgery in an efficient system. METHODS: All patients with isolated hip fracture admitted to a regional trauma center from April 1993 to March 2003 were reviewed. Demographics, presence of comorbidity, preoperative delay, complications, and mortality were collected. Univariate and multivariate analysis were carried out. RESULTS: The cohort included 977 patients. Overall mortality was 12.2%. Surgery was performed within 24 hours in 53% of cases and within 48 hours in 87% of cases. The presence of comorbidity partly explained longer (>48 hours) surgical delays. Multivariate analysis revealed that age greater than 65, male sex, and the presence of pulmonary and cardiac comorbid conditions or an active cancer but not surgical delay were associated with mortality and complications. However, surgical delay was associated with longer postsurgical hospital stay, independently of the presence of comorbidity or increasing age. CONCLUSIONS: Preoperative delay does not entail adverse outcomes when the surgery is delayed to allow for treatment of comorbid medical conditions. Preoperative delay is associated with a longer hospital stay. The presence of comorbidity only partly explains preoperative delay and adverse outcomes. A prospective study coding for the severity of comorbid conditions and the justification of the preoperative delay will be required to fully elucidate the link between delay and outcome.

Adult↗

PubMed2006

Clinical judgment remains of great value in the diagnosis of acute appendicitis.

BACKGROUND: Observation and repeated examination may lead to favourable clinical outcomes in the ever-challenging diagnosis of appendicitis. The goal of this study was to evaluate clinical performance in the diagnosis of suspected appendicitis in a centre with limited access to medical imaging technologies and to identify factors associated with complicated cases. METHODS: A retrospective review of the medical records of 211 consecutive surgical cases of suspected appendicitis, spanning an 11-year period, was performed. The delays before treatment and the subsequent patient outcomes were evaluated. RESULTS: There were 8.1% of cases with negative findings on appendectomy, 75.8% with uncomplicated appendicitis, 12.3% with complicated appendicitis and 3.8% with other surgical conditions. The delay before the first medical consultation was significantly longer in patients with complicated appendicitis. The various delays after the first medical consultation did not differ significantly between the groups. CONCLUSIONS: In the context of limited available medical imaging modalities, clinical observation was not associated with an increased incidence of complicated appendicitis. The presence of complicated appendicitis was associated with the delay before the patient's first medical consultation. Clinical judgment can be prioritized and can lead to good clinical performance in the management of patients with suspected appendicitis, with no significant increase in rates of complicated appendicitis and negative findings on appendectomy.

Acute Disease↗

PubMed2006

Consensus or data-derived anatomical severity scoring?

We aimed to compare the predictive accuracy of consensus-derived and data-derived injury severity scores when considered alone and in combination with age and physiological status. Analyses were based on 25,111 patients. The predictive validity of each severity score was evaluated in logistic regression models predicting in-hospital mortality using measures of discrimination and calibration. Data-derived scores had consistently better predictive accuracy than consensus-derived scores in univariate models (p<0.0001) but very little difference between scores was observed in models including information on age and physiological status. Data-derived scores provide more accurate mortality prediction than consensus-derived scores when only anatomic injury severity is considered but offer little advantage if age and physiological status are taken into account.

Adolescent↗

PubMed2005

Chloroquine is a potent inhibitor of SARS coronavirus infection and spread.

BACKGROUND: Severe acute respiratory syndrome (SARS) is caused by a newly discovered coronavirus (SARS-CoV). No effective prophylactic or post-exposure therapy is currently available. RESULTS: We report, however, that chloroquine has strong antiviral effects on SARS-CoV infection of primate cells. These inhibitory effects are observed when the cells are treated with the drug either before or after exposure to the virus, suggesting both prophylactic and therapeutic advantage. In addition to the well-known functions of chloroquine such as elevations of endosomal pH, the drug appears to interfere with terminal glycosylation of the cellular receptor, angiotensin-converting enzyme 2. This may negatively influence the virus-receptor binding and abrogate the infection, with further ramifications by the elevation of vesicular pH, resulting in the inhibition of infection and spread of SARS CoV at clinically admissible concentrations. CONCLUSION: Chloroquine is effective in preventing the spread of SARS CoV in cell culture. Favorable inhibition of virus spread was observed when the cells were either treated with chloroquine prior to or after SARS CoV infection. In addition, the indirect immunofluorescence assay described herein represents a simple and rapid method for screening SARS-CoV antiviral compounds.

Ammonium Chloride↗

PubMed2005

Implication of proprotein convertases in the processing and spread of severe acute respiratory syndrome coronavirus.

Severe acute respiratory syndrome coronavirus (SARS-CoV) is the etiological agent of SARS. Analysis of SARS-CoV spike glycoprotein (S) using recombinant plasmid and virus infections demonstrated that the S-precursor (proS) exists as a approximately 190 kDa endoplasmic reticulum form and a approximately 210 kDa Golgi-modified form. ProS is subsequently processed into two C-terminal proteins of approximately 110 and approximately 80 kDa. The membrane-bound proprotein convertases (PCs) furin, PC7 or PC5B enhanced the production of the approximately 80 kDa protein. In agreement, proS processing, cytopathic effects, and viral titers were enhanced in recombinant Vero E6 cells overexpressing furin, PC7 or PC5B. The convertase inhibitor dec-RVKR-cmk significantly reduced proS cleavage and viral titers of SARS-CoV infected cells. In addition, inhibition of processing by dec-RVKR-cmk completely abrogated the virus-induced cellular cytopathicity. A fluorogenically quenched synthetic peptide encompassing Arg(761) of the spike glycoprotein was efficiently cleaved by furin and the cleavage was inhibited by EDTA and dec-RVKR-cmk. Taken together, our data indicate that furin or PC-mediated processing plays a critical role in SARS-CoV spread and cytopathicity, and inhibitors of the PCs represent potential therapeutic anti-SARS-CoV agents.

Animals↗

PubMed2005

Should patients with isolated hip fractures be included in trauma registries?

BACKGROUND: Patients with isolated hip fractures are frequently excluded from trauma registries. The goal of this study was to show that patients with these injuries have higher resource use and poorer outcomes than the rest of the trauma population. METHODS: The Quebec Trauma Registry was used to identify all trauma patients from April 1, 1998, to March 31, 2003. Patients who were dead on arrival at the emergency room were excluded. Isolated hip fracture (HIP) was defined as a diagnosis of a single fracture to the neck of the femur (Abbreviated Injury Scale 1990 codes 851808.3, 851810.3, 851812.3, and 851818.3) secondary to a fall and for which the Injury Severity Score was 9 or 10 (no other Abbreviated Injury Scale code higher than 1). Patients with all other trauma diagnosis (OT) were used for comparison. Outcome variables were length of hospital stay, length of intensive care unit (ICU) stay, in-hospital complications, and status and orientation at discharge. Chi-square and Wilcoxon rank-sum tests were used. RESULTS: There were 68,422 patients: 14,426 (21.1%) HIP patients and 53,996 (78.9%) OT patients. The median Injury Severity Score was 9 for HIP (range, 9-10) and 9 for OT (range, 1-75). Mean length of hospital stay was 18.4 days for HIP compared with 11.7 days for OT (p < 0.0001). HIP patients represented 29.5% of the total hospital stay. ICU stay was required for 1,353 HIP patients (9.4%) and for 12,395 (23.0%) OT patients (p < 0.0001). Mean ICU stay was 3.9 days for HIP compared with 5.5 days for OT (p = 0.0006). In-hospital mortality was 8.5% in HIP compared with 3.7% in OT (p < 0.0001). HIP represented 62.7% of patients referred for long-term care and 39.3% of patients referred to a rehabilitation center. CONCLUSION: Patients with HIP represented 21.1% of admissions while accounting for 42% of total days of hospitalization and 38% of deaths. Patients with hip fractures have a significantly higher risk of death, prolonged hospital stay, and complication rate, and are more often transferred to a rehabilitation center or to a long-term nursing home than the rest of the trauma population despite lower severity. They require multidisciplinary care typical of the rest of the trauma population and should be included in the trauma registry if the registry is to document the full outcome and resource use of the trauma population.

Adult↗

PubMed2005

Penetrating thoracoabdominal injuries in Quebec: implications for surgical training and maintenance of competence.

BACKGROUND: The frequency of penetrating trauma is low in Canada. Current recommendations for the care of patients with penetrating injuries originate from inner city trauma centres with a high volume of such injuries and may not apply to Canada. The purpose of this study was to review the incidence and treatment of penetrating thoracoabdominal injuries in the 4 tertiary trauma centres in Quebec. METHODS: We identified all patients with penetrating thoracic or abdominal injuries who were taken to any of the 4 tertiary trauma centres in the province of Quebec between Apr. 1, 1998, and Mar. 31, 2001. Patients who were dead on arrival were excluded. Only patients with an Abbreviated Injury Scale of 2 or greater for the thoracic or abdominal regions were included. RESULTS: In total, 245 patients meeting our inclusion criteria were identified. Of these 223 (91%) were male. The mean (and standard deviation) age was 33.8 (13.2) years; range 15-90 years. The median Injury Severity Score was 10 (range 4-75). Overall in-hospital mortality was 6.9%. There were 203 patients (82.8%) with thoracic injuries and 192 patients (78.4%) with abdominal injuries. Fifty (20.4%) of these patients had injuries to both regions. A thoracotomy was carried out in 48 (31.4%) of 153 patients who had injuries to the thorax, and the abdomen was explored in 133 (93.7%) of the 142 patients with abdominal injuries. The incidence of these injuries in the study period varied from 3 to 49 cases per centre. CONCLUSIONS: The annual incidence of penetrating thoracoabdominal injuries is extremely low in all 4 of Quebec's tertiary trauma centres, and the number of thoracoabdominal procedures is even lower. Such a low exposure may jeopardize education and clinical competence. We need to rethink our educational strategies both for residents and for continuing medical education. New approaches to training and maintenance of competence must be developed.

Abdominal Injuries↗

PubMed2005

A second injury in the same body region is associated with lower mortality than a second injury in a different body region.

HYPOTHESIS: A second injury in the same body region is associated with lower mortality than a second injury in a different body region, independently of injury severity and body region. METHODS: The population consisted of 15,200 patients with two or more injuries from level I trauma centers in Quebec. The mortality odds ratio of having a same-region second injury (SR) as opposed to a different-region second injury (DR) was assessed. RESULTS: Patients with a SR had 43% lower odds of mortality when compared to patients with a DR. CONCLUSION: A second injury in the same body region is associated with lower mortality than a second injury in a different body region.

Accidents, Traffic↗

PubMed2005

Comorbidity and age are both independent predictors of length of hospitalization in trauma patients.

BACKGROUND: Length of hospitalization is a good indicator of resource utilization. Older patients are increasingly suffering trauma, and comorbid medical conditions are also increasing. Our objective was to determine the separate and combined effect of these 2 factors on length of hospital stay for trauma patients in a tertiary trauma centre. METHODS: All 994 consecutive trauma patients surviving to hospital discharge between Apr. 1, 2000, and Mar. 31, 2001, were identified. Patient characteristics, injury severity and length of hospitalization were obtained from the hospital trauma registry. Each medical record was then reviewed for completeness of information and assessment of comorbid conditions. A multivariate linear regression model was developed to predict logarithmic length of stay from age and presence of a cormorbid condition while adjusting for the Injury Severity Score (ISS). RESULTS: The mean age of the patients was 49.7 (range from 14-100) years and median ISS was 9 (range from 1-50). At least 1 comorbid condition was present in 321 (32%) patients. Mean length of hospital stay was 15.3 days. The proportion of patients with a comorbid condition increased steadily with age, from 8.7% before the age of 55 years to 92% at 85 or more years of age (p < 0.001). According to the multivariate model, the presence of comorbidity, age and ISS were all independent predictors of hospital stay (p < 0.001). When applied to patients with the mean ISS value of 9, the model showed an increase in length of hospitalization for patients with a comorbid condition over those without; (3.6 v. 13.1 d for patients < 55 and > or = 85 yr respectively). Length of hospital stay increased particularly with neurologic and pulmonary problems. CONCLUSIONS: Comorbidity and age were both independently significant predictors of length of hospitalization over and beyond that which is expected based on the severity of the injuries. With an aging population, this phenomenon should severely affect resource utilization in trauma centres in the near future. Researchers should take account of both age and comorbidity in order to compare trauma populations.

Adolescent↗

PubMed2005

Multiple imputation of the Glasgow Coma Score.

BACKGROUND: To investigate whether multiple imputation (MI) of missing Glasgow Coma Scale (GCS) values generates more accurate GCS frequency distributions and less biased parameter estimates in logistic regression models predicting mortality than the standard procedure of excluding observations with missing GCS values. METHODS: The study population consisted of 5,065 patients with complete GCS information from the trauma registry of a Level 1 trauma center. Missing GCS values were imposed on the data set, and the performance of MI (extrapolating missing GCS from a data prediction model) and of deleting all data observations with missing GCS (list-wise deletion) were evaluated. GCS and Trauma and Injury Severity Score (TRISS) frequency distributions and parameter estimates were compared with true values from the original data set. RESULTS: GCS and TRISS frequency values generated by MI were much more accurate than those generated by list-wise deletion. GCS and TRISS parameter estimates generated by MI all had acceptable bias and coverage rates when compared with true values. List-wise deletion provided biased parameter estimates for the GCS, the Revised Trauma Score, and the Injury Severity Score. CONCLUSION: MI is a valid solution to the problem of missing GCS data in trauma research. It allows the conservation of precious data observations and leads to unbiased estimates in consequent analyses. Analyses, which exclude observations with missing GCS data, provide biased results.

Biomedical Research↗