Dear Editor,
We appreciate Jalaber et al. consideration of our study in their paper on the role of CT imaging in diagnosing COVID-19 pneumonia [1]. The authors report that CT chest in the diagnosis of COVID-19 pneumonia may yield a poor specificity due to a high rate of false positives [1]. This conclusion was based on the ‘Living’ Cochrane Systematic Review on the diagnostic accuracy of imaging tests for COVID-19, published in November 2020, which identified that chest CT had a specificity of 61.1% (95% confidence interval (95% CI 42.3 to 77.1) and sensitivity of 89.9% (95% CI 85.7 to 92.9) [2].
This ‘Living’ Cochrane Systematic Review has aimed to keep up with the evidence as research in this field is rapidly progressing. The most recent version was published in March 20213 which identified that specificity of chest CT has increased substantially with a small rise in sensitivity. Our meta-analysis which included 41 studies and 16,133 participants found that the specificity of chest CT was 80.0% (95% CI 74.9-84.3) and the sensitivity was 87.9% (95% CI 84.6-90.6) [3]. The improved performance – specificity in particular – could be due to the widespread use of scoring systems (such as CO-RADS) that provide definitions for index test positivity. Another likely explanation is the improved quality of evidence available at a later stage in the pandemic for new studies [4]. In addition, our latest update included an evaluation of the performances of the diagnostic accuracy of chest x-ray and ultrasound for COVID-19. In the future, we hope that methodological rigour and transparent reporting will be prioritized by all authors. We appreciate the interest in our work and our Cochrane team will continue to provide up to date evidence on the diagnostic accuracy of these imaging modalities.
Disclosure of interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
References
- 1.Jalaber C., Chassagnon G., Hani C., Dangeard S., Babin M., Launay O., et al. Is COVID-19 pneumonia differentiable from other viral pneumonia on CT scan? Respirat Med Res. 2021;79 doi: 10.1016/j.resmer.2021.100824. Advance online publication. [DOI] [PMC free article] [PubMed] [Google Scholar]
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- 3.Islam N., Ebrahimzadeh S., Salameh J.P., Kazi S., Fabiano N., Treanor L., et al. Thoracic imaging tests for the diagnosis of COVID-19 (Update 2) Cochrane Database Syst Rev. 2021;3(3) doi: 10.1002/14651858.CD013639.pub4. [DOI] [PMC free article] [PubMed] [Google Scholar]
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