Comparison of tomographic reports by radiologists and non-radiologists in trauma and interferences in management in a trauma reference center

ABSTRACT Objective: diagnostic errors during the interpretation of an imaging test by the physician can lead to increased mortality and length of hospital stay for patients. The rate of divergence in the report given by a radiologist and an Emergency Physicians (EP) can reach over 20%. The objective of this study was to compare the unofficial tomographic reports issued by EP with the official reports issued by radiologists. Methods: a cross-sectional study, in which interpretations of the exams (documented in the medical records by the EP) of all patients undergoing computed tomography (CT) of the chest, abdomen or pelvis performed in the emergency room, at an interval of 8 months, were evaluated. These data were compared with the official reports of the radiologist (gold standard). Results: 508 patients were included. The divergence between EP and the radiologist occurred in 27% of the cases. The most common type of divergence was the one not described by the EP, but described by the radiologist. The chance of having divergence in a case of multiple trauma is 4.93 times greater in relation to the case of only blunt trauma in one segment. A statistically relevant difference was also found in the length of stay of patients who had different interpretations of the CT scans. Conclusion: the study found a relatively high divergence rate between the EP report and the official radiologist report. However, less than 4% of these were considered to be clinically relevant, indicating the ability of the EP to interpret it satisfactorily.


INTRODUCTION
T he beginning of the study of radiological errors dates to 1899, with Beclere1 , who analyzed the time it takes the retina to evaluate a fluoroscopic screen with adequate sensitivity.That study found that only after 20 minutes the retina has its maximum sensitivity, allowing the presence of interpretation errors before this interval, culminating in misdiagnosis.
Diagnostic errors are a key component of medical error, representing up to 37% of that category 2 .In addition to causing an increase in mortality, diagnostic errors also increase patients' length of stay, burdening health systems 3 .Medical malpractice moves millions of dollars annually in the judicial sphere and the focus of lawsuits is on emergency physicians (EP) 2 .This is due to the pressure exerted on this class and to the fatigue to which professionals are subjected to 4 .Most emergency rooms (ERs) do not have a radiologist readily available to interpret the requested imaging tests.Thus, in the urgency/emergency scenario, the EP initially interprets most exams, with the official report issued later by the radiologist.This is particularly important in trauma care services, as this type of care requires quick and assertive decisions.When analyzing 1,522 radiological exams, Mattsson and colleagues found a Gabriel Mondin noGueira 1 ; leonardo KrieGer rafael 1 ; Gabriel Sebben reichardt 1 ; MateuS dall'aGnol 1 ; Silvania KluG PiMentel tcbc-Pr 2 .
divergence rate of 20.35% between interpretations, with approximately one third of them being clinically significant 5 .Factors such as the patient's age and studied anatomical region were risk predictors for the occurrence of discrepancies 5 .The occurrence of divergences also varies according to the type of exam.
A 2019 study found a 6.5% rate of divergence between the interpretation of radiographs, indicating that the EP can interpret this exam with relative safety 6 .The type of sustained injury is also relevant when considering the number of discrepancies.A study conducted in South Africa analyzed only CT scans of polytrauma patients and found a concordance rate between the radiologist and the EP of only 58.6% 7 .However, only 4.84% of the patients were victims of a clinically relevant discrepancy, which was not statistically significant (p>0.05) 7.The objective of this study was to compare the unofficial CT reports issued by the EP in the emergency department of a reference trauma center with the official reports issued by radiologists, analyzing their divergences and their clinical significance.We also analyzed the risk factors for the occurrence of such discrepancies.

METHODS
This is a cross-sectional study conducted in a referral center for trauma care in the city and metropolitan region of Curitiba, State of Paraná, Brazil.Within an interval of eight months (10/01/2019-05/26/2020), we evaluated the medical records of all patients who underwent computed tomography (CT) of the chest and/ or abdomen and/or pelvis performed in the emergency room.We reviewed the interpretations of the exams documented in the medical records by the EP (nonofficial report) and the conduct taken based on them.We then compared these data with the radiologists' official reports, considered the gold standard.In cases where there was disagreement between the two interpretations, an experienced trauma surgeon analyzed the clinical significance of the disagreement independently.In cases where a sole case generated more than one discrepancy, we counted the discrepancy only once.We included patients over 18 years old (age at the time of collection) who underwent tomography of the chest and/or abdomen and/or pelvis in the period from 10/01/2019 to 05/26/2020.The exclusion criteria adopted were tomography performed for reasons unrelated to trauma, transcription of a verbal report provided by a radiologist simultaneously with the evaluation of the image by the EP, absence of an official CT report, lack of evaluation by the general surgery team, and return of the patient after previous trauma.In addition to the evaluation of the tomographic findings and their divergences, we analyzed patients' gender and age, mechanism of trauma, type of trauma, time and date of the unofficial evaluation and date of the official evaluation, length of stay, and outcome.For a better evaluation, we divided the day into the following periods: morning (8h-12:59h); afternoon (1pm-5:59pm); night (20h-00:59h); and early morning (01h-05:59h).We also defined the periods close to the shift change in the morning (6:00 am to 7:59 am) and in the afternoon (6:00 pm to 7:59 pm).
We considered divergences both the findings described by the radiologist and not by the EP and those that the EP described, and the radiologist did not.We divided the trauma mechanisms into categories, namely fall from the same level (FSL), fall from another level (FAL), stab wound (SW), gunshot wound (GSW), overturning, runover, car accidents, assaults, colliding with an object, hanging, crushing, motorcycle fall, horse fall, and bicycle fall.We reduced the variable type of trauma to blunt, open, or multiple trauma types.Polytrauma patients were those who suffered injuries in at least two different systems.
When evaluating the official report, we considered only injuries related to the current trauma, disregarding old or clinical alterations.For age, we tested the null hypothesis that the age means are the same for non-divergent and divergent cases, versus the alternative hypothesis that the means are different.In addition, we tested the null hypothesis that the probabilities of death are the same for cases with and without divergence, versus the alternative hypothesis of different probabilities.For each of the categorical variables, we tested the null hypothesis that the probabilities of divergence between EP and Radiologist are the same for all classifications of the variable, versus the alternative hypothesis that the probabilities are different.We described quantitative variables by mean and standard deviation or by median, minimum, and maximum.We described categorical variables by frequency and percentage.To assess the Nogueira Comparison of tomographic reports by radiologists and non-radiologists in trauma and interferences in management in a trauma reference center association between demographic and clinical variables and the divergence between EP and Radiology, we fitted Logistic Regression models.We used the Wald test to analyze the significance of the variables.The estimated measure of association was the odds ratio, for which we computed 95% confidence intervals.We analyzed the association between divergence and death with the Fisher's exact test.For the comparison between cases with and without divergence regarding length of stay, we used the non-parametric Mann-Whitney test.
Values of p<0.05 indicated statistical significance.We analyzed the data using the Stata/SE v. 14

RESULTS
WE analyzed 1,177 tomography records and, after applying the exclusion criteria, 508 patients formed the study group, of whom 78.1% (n=397) were male.
The comparison between polytrauma and blunt trauma showed statistical significance (p<0.001).The chance of divergence in a case of polytrauma was 4.93 times higher than the case of only blunt trauma in one segment (Table 4).There was also a longer hospital stay in cases of polytrauma.Also, we found no significant association between divergence and death.We observed a statistically significant difference (p<0.001) in the length of stay of patients who had divergent interpretations of CT scans (mean of 6.6 days of hospitalization) when compared with those with concordant interpretations (mean of 1.1 days of hospitalization).These results are shown in Table 5.Of the 137 cases with disagreement, five (3.64%) were judged to be clinically significant.

DISCUSSION
Radiology is an important ally during the diagnostic evaluation in trauma care.However, in developing countries like Brazil, there is not always a radiologist readily available in all trauma care services8.
Issues such as fatigue and the complexity of the cases may be capable of increasing the incidence of divergences 4,9 .We analyzed the period of the day when the tomography was performed and the type of trauma in an unprecedented way.It is important to emphasize that the EP did not have formal training in Radiology, acquiring their experience during residency and throughout their careers.This study demonstrated that in terms of epidemiology, when analyzing the profile of patients undergoing tomography, there was a higher incidence of trauma in males, most of which were blunt and due to car collisions, which is consistent with the literature [10][11][12] .There was divergence between the EP assessment and the Radiologist's report in 27% (n=137) of the cases, consistent with literature data 5 .
When we analyzed their clinical relevance, the number dropped to just 0.98% (n=5).The most common type of divergence was the false negative, in which the Radiologist described the alteration in the exam and the EP did not.
Although foreseen, documentation bias should also be considered.Contrary to what was expected, variables such as the patient's age and time of day when the care was provided did not show a statistically significant increase in the divergence rate.As older patients have more associated diseases 13 (distracting for those who analyze the tomography), we thought that would cause a greater number of discrepancies 5 .However, we did not observe this increase.The fact that the time of day did not change the divergence rate in a relevant way indicates that fatigue, in the specific conditions in which the on-call physicians were, was not a determining factor for the quality of interpretation of the image exams, which contradicts the data currently present in the literature 4,14,15 .Furthermore, there was no statistically significant association between the divergence rate and death, indicating that the types of divergence found were not relevant enough to change patients' final outcomes.
When analyzing the type of trauma suffered, polytrauma, in addition to demonstrating a longer average length of stay, also determined a greater chance of occurrence of divergences (OR=4.93).In addition, there was a statistically significant relationship (p<0.001) between length of stay and the number of discrepancies found.However, we believe that the positive relationship between length of stay and the number of discrepancies found is because patients hospitalized for a longer time have a greater number of injuries, which increases the chance of them missing in the medical record (EP describing only the most important lesions).That is, the divergence found was not necessarily the causal agent of the longer hospital stay.In addition, physicians on duty, according to their experience, develop the ability to describe in the medical record only the injuries effectively capable of altering the prognosis of critically ill patients.
Thus, many divergences found may be because the EP interpret the injury as insignificant, and not due to the lack of perception of the injury itself.
Of the 137 divergence cases found in the study, only five (0.98%) were clinically significant.Even though the data on divergences agree with the literature, the percentage of clinically significant divergences was significantly lower than another retrospective study (10.88%) 5 and a prospective cohort (4.84%) 7 .Despite the occurrence of these cases, it is not possible to state that these divergences caused more morbidity and mortality, due to the retrospective nature of the study.The study has limitations, a retrospective bias 16 and a documentation one, in which the EP may have described only the most important injuries, not documenting other findings.Likewise, there is the possibility of prior discussion about the case between the EP and the Radiologist, without reporting this in the medical record.Another limitation is that the study analyzed only CT scans of the thorax, abdomen, and pelvis, and did not consider other imaging modalities or even other evaluation sites, such as the head.The evaluation of only one trauma care center also limits this study.

CONCLUSION
Although the study found a high rate of divergence between the EP reports and the Radiologists' official reports, a small portion of these was clinically relevant.This demonstrates the attendants' ability to satisfactorily interpret the images of the main lifethreatening conditions in trauma.

R E S U M O R E S U M O
.1 software, StataCorpLP, USA.The study was approved by the Ethics Committee of Hospital do Trabalhador under number 32122820.8.0000.5225.

Table 1 -
Type of divergence.
*Both professionals described different injuries.

Table 2 -
Type of divergence.NogueiraComparison of tomographic reports by radiologists and non-radiologists in trauma and interferences in management in a trauma reference center

Table 3 -
What the EP described, and the Radiologist did not describe *Percentages calculated on the total number of cases considered (n=38).
Table 6 brings their characteristics.Nogueira Comparison of tomographic reports by radiologists and non-radiologists in trauma and interferences in management in a trauma reference center