Note: The risk of bias by domain corresponds to the highest risk of bias among outcomes by domain.
The overall risk of bias corresponds to the overall highest risk of bias assessed among outcomes.
| 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. 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 |