| Bias | Author's judgement | Support for judgement |
| Randomization |
Low |
Quote: "Randomization was stratified by the center and oxygen therapy (nasal cannula or mask, or high-flow oxygen, noninvasive ventilation). A statistician who was masked to trial allocation generated the permuted block (4 patients per block) randomization sequence by using SAS software (version 9.4; SAS Institute). Randomization was conducted by using the Interactive Voice Response service provided by Guangzhou University. The allocation team was masked to the block size and random allocation table."
Comment: Allocation sequence random. Allocation sequence concealed. |
| Deviations from intervention |
Some concerns |
Comment: Unblinded study.
Two participants who were allocated to the intervention group did not receive the intervention. Deviation too small to affect the outcome. Co-intervention administration of corticosteroids and antivirals are reported. No information on biologics and anticoagulants. Data were analyzed using intention-to-treat analysis. |
| Missing outcome data |
Low |
Comment: 200 patients randomized; 200 patients analyzed.
Risk assessed to be low for outcomes: Mortality. Time to death. Time to clinical improvement. Adverse events. Serious adverse events. |
| Measurement of the outcome |
Some concerns |
Comment: Unblinded study.
Mortality is an observer-reported outcome not involving judgement. Risk assessed to be low for outcomes: Mortality. Time to death. Clinical improvement (defined as at least one point improvement on a seven point scale or discharge) reflects a decision made by the intervention provider where the assessment could possibly be influenced by knowledge of the intervention assignment however we did not consider this likely in the context of a pandemic. Adverse events and serious adverse events may contain both clinically- and laboratory-detected outcomes, therefore it can be influenced by knowledge of the intervention assignment, but is not likely to. Risk assessed to be some concerns for outcomes: Time to clinical improvement. Adverse events. Serious adverse events. |
| Selection of the reported results |
Low |
Comment: The protocol and statistical analysis plan were available. Outcomes reported as pre-specified.
Risk assessed to be low for the outcomes: Mortality. Time to death. Time to clinical improvement. Adverse events. Serious adverse events. |
| Overall risk of bias |
Some concerns |