Critical appraisal of research articles is an important process that is used to inform practice. This critical process is carried out with caution and in a systematic manner to determine the trustworthiness, relevance, and value of evidence in a particular context (Mhaskar et al., 2009). Hence, this paper aims to critically appraise an article, “What is the clinical significance of chest CT when the chest x-ray result is normal in patients with blunt trauma?” by Kea and others, published in 2013.
What is the clinical significance of chest CT when the chest x-ray result is normal in patients with blunt trauma?
Kea et al. (2013) aimed at determining the essence of computed tomography even after patients with blunt trauma had received normal chest x-ray results.
Strengths and Weaknesses of the Study
The article adapted a retrospective research design because it used retrospective data to develop and analysis (NEDARC, 2010). The challenge with retrospective data is that it may not reflect current protocols that are in alignment with current times; hence, introducing some bias. In this study, there was no intervention used though two groups for comparison purposes were identified; one underwent only a chest x-ray (CXR) procedure while the other one underwent both the CXR and CT. However, there is insufficient information given on the nature of the two groups in reference to characteristics and clinical outcomes. The study is not related to the topic of the research article because the title of the article depicts a study that determines to establish a causal link, but the methodology is not rigorous enough to establish this link (Salkind, 2010). The study setting is indicated, and it was conducted at two locations: California, San Francisco General Hospital and Community Regional Medical Center in Fresno that are urban, level 1 trauma centers.
Even though the current study was not part of another study, it utilized a sample from a previous study aimed at developing a decision instrument for selective chest X-ray imaging in blunt trauma. Whereas this is one approach that can be used to obtain a sample size, using the exact sample size used in a previous studies is not recommended though variance, standard deviation, or statistical power from previous studies can be used to determine sample size in a current or future study. Therefore, the manner in which the sample size for the article being reviewed was obtained is not as per the recommendations (Suresh & Chandrashekara, 2015). Therefore, it is difficult to determine whether the sample was sufficient or not. An articulate inclusion criteria is indicated, but a clear exclusion criteria is lacking; hence, the study might be prone to confounding factors if a patient has an ailment that might be associated with occurrence of minor injuries to the chest as indicated by Veronesi (2004). The sample section does not describe the use of two groups; hence, there is minimal information on the two groups mentioned later in the results section. The main exclusion criteria was unavailability of patient data, which is not sufficient considering that other factors might interfere with the results. The nature of the study participants, nonetheless, was suitable to the aim of the study that sought to determine the effect of CT; thereby, comparing a CT group with a CXR group is desirable.
Radiologic outcomes were determined using “official radiologic reports by board-certified radiologists.” Such a measurement scale that has gained approval is deemed a valid and reliable tool though this information is not provided in this study. However, the instrument used to determine clinical significance of the CT was developed during the study, but there is no mention about its validity and reliability. Thereby, use of an outcome measure whose validity and reliability is not known jeopardizes the results.
Apparently, two groups were recruited, but the study does not indicate the statistical difference in outcomes among the two groups. Rather, the results section explains the confirmations and missed diagnosis in the group that had both the CXR and CT. It is not clear how the two groups were selected and their comparability at the beginning of the study. In addition, the two groups are not of proportionate sizes, and there is no indication whether such non-uniformity has significant effects on comparability of the groups. There is no indication that an ethical approval was obtained and even though the researchers did not directly interact with participants, they accessed sensitive documents that should be handled with confidentiality and privacy should be upheld (“Ethics approval of research,” 2017).
The results of this study are not generalizable because there is sampling bias, and the assignment of the two groups is not done in a scientific manner as indicated by Viera and Bangdiwala (2007). In addition, the fact that this study is retrospective in nature is associated with bias because the kind of treatment given to the different individuals varied. Hence, it is not apparent that all individuals in the different groups followed a similar protocol based on the procedure (s) carried out. It is not clear what the clinically important injuries that are detectable using the CT and not the CXR are and the net benefit they have as Korley, Pham, and Kirsch (2010) highlight. The results obtained from this study cannot inform policy because the reliability and validity of measures used are not known.
Implications to Practice
The key findings of the article under review are in alignment with findings from other studies in that computed tomography is linked with detection of more chest injuries than normal chest x-ray, but these injuries are minor such that they do not warrant improved management. This study stems from improved technology that has led to increased availability and rapidity of the CT scans but they have no clinical significance. This study is important to practice because it helps to determine the necessity of CT scans compared to the typical chest X-rays. Thereby, practitioners are able to know whether it makes a difference to replace the normal chest x-ray machines with the CT scan equipment. In view of the fact that there are no standard significant changes when performing x-rays, the instrument to determine these outcomes is not widely accepted. In view of the fact that computed tomography (CT) has a high sensitivity in radiology for blunt trauma, other investigators regard its use to be of little significance to management of these injuries since CT is deemed a high risk factor of cancer. Hence, it is imperative to determine the net effect of CT to avoid the high costs that can emerge from its use.
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Kea, B., Gamarallage, R., Vairamuthu, H., Fortman, J., Lunney, K., Hendey, G. W., Rodriguez, R. M. (2013). What is the clinical significance of chest CT when the chest x-ray result is normal in patients with blunt trauma? American Journal of Emergency Medicine, 31, 1268-1273.
Korley, F. K., Pham, J. C., & Kirsch, T. D. (2010). Use of advanced radiology during visits to US emergency departments for injury-related conditions, 1998-2007. JAMA, 304, 1465–71.
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Veronesi, J. F. (2004). Trauma nursing: Blunt chest injuries. Retrieved from chest-injuries.
Viera, A. J., & Bangdiwala, S. I. (2007). Eliminating bias in randomized controlled trials: Importance of allocation concealment and masking. Family Medicine, 39(2), 132-137.