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 |
Some concerns |
Quote: "Participants were randomly assigned in a 1:1 ratio to receive a single dose of NVX-CoV2373 or
BBIBP-CorV."
Comment: Allocation sequence probably random. No information on allocation concealment Imbalances in baseline characteristics appear to be compatible with chance |
| Deviations from intervention |
Low |
Quote: “In this interim analysis of a randomized, observer-blinded clinical trial”
Comment: Unclear blinding Deviations from intended intervention arising because of the study context: No participant cross-over. Hence, deviations did not arise because of the trial context Intention-to-treat analysis was reported for all the outcomes. As we are assessing the effect of assignment to intervention, the analysis method performed on these safety outcomes, was considered appropriate. Risk assessed to be low for the outcomes: Specific antibody GMT. Neutralizing antibody GMT. Adverse events. Serious adverse events. |
| Missing outcome data |
Low |
Comment: 1000 participants randomized; 998 participants analyzed for safety outcomes, 912 participants analyzed for immunogenicity outcomes
ADVERSE EVENTS, SERIOUS ADVERSE EVENTS Data available for all or nearly all participants randomized. Risk assessed to be low for the outcomes: Adverse events. Serious adverse events. SPECIFIC ANTIBODY GMT. NEUTRALIZING ANTIBODY ASSAY GMT Data not available for all or nearly all participants randomized. No evidence that the result is not biased. Reasons: deviations from protocol. Risk assessed to be some concerns for the outcomes: Specific antibody GMT. Neutralizing antibody GMT. |
| Measurement of the outcome |
Low |
Comment: Method of measuring the outcome probably appropriate.
Measurement or ascertainment of outcome probably does not differ between groups. Blinded study (outcome assessor). Risk assessed to be low for the outcomes: Specific antibody GMT. Neutralizing antibody GMT. Adverse events. Serious adverse events. |
| Selection of the reported results |
Low |
Comment: The registry was available (February 22, 2022).
Outcomes pre-specified. Results were not selected from multiple outcome measurements or analyses of the data. Trial analyzed as pre-specified. [go to Risk assessed to be low...] Risk assessed to be low for the outcome: Specific antibody GMT. Neutralizing antibody GMT. Adverse events. Serious adverse events. |
| Overall risk of bias |
Some concerns |