RR:C19 Evidence Scale rating by reviewer:
Not informative. The flaws in the data and methods in this study are sufficiently serious that they do not substantially justify the claims made. It is not possible to say whether the results and conclusions would match that of the hypothetical ideal study. The study should not be considered as evidence by decision-makers.
This Manuscript describes an RNA extraction Kit-free protocol for the detection of COVID-19 RNA in nasopharyngeal swaps. The proposed method was used to analyse 100 samples and compare results to reference standard RT-PCR after RNA extraction. Samples were subjected to an optimized RNA-precipitation and washing with heat shock at 90°C. Authors claim a specificity of 100% when compared to Perkin Elmer© COVI-19 diagnostic test after analysis of 100 patient samples. There are concerns related to the sample collection and ethical approval for this process that has not been mentioned at all throughout. The novelty of the work is also questionable, since isopropanol-based protein and nucleic acid precipitation is well known for at least a decade now. On the other hand, the developed protocol does not appear to support claims authors made that this approach will allow decreasing the assay time, reduce cost and instrumentation, as it still requires RT-PCR assay to quantify viral RNA. In addition, most current extraction procedures are done in a small vial, and in majority of cases, it is not the rate determining step in the assay turnaround time. With previous considerations, I do not see the advantage of this protocol over current COVID-19 diagnostic technologies specially those not requiring a pre-extraction step like Abbott© ID Now. I do consider this study as not informative especially with absence of any raw data required for clinical assessment of the results validity and absence of ethical approval for human sample collection and analysis. I would not recommend publishing this manuscript in its current format.