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It is remarkable that in a randomised trial, when only chance may have introduced differences between groups, authors go out of their way to present a long list of baseline characteristics to lend credibility to the fairness of comparing outcome occurrence between groups, where here, in a non-randomised comparison of patients from different centres who clearly do differ, authors have not made the slightest effort to present such baseline characteristics. The reviewer can only come to the conclusion that the comparison
with the control group is meaningless.
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It is reported that 42 patients met the eligibility criteria, and of these 16 were in the control group, and 26 in the treated group. Of these 26, six were excluded (and incorrectly labelled as lost to follow-up): three were transferred to the ICU, one died, and two terminated treatment or were discharged. Firstly, it is noteworthy that 4/26 treated patients
deteriorated and 0/16 control patients, which emphasises that the groups were different. More importantly, excluding patients who deteriorated from the analyses introduces severe selection bias, since it selectively excludes people who did not do well (as an extreme example: if 25/26 treated patients had died, and one had virus clearance at day 6, would a claim of 100% clearance be valid?).
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