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|
|Quote: “Participants were randomly assigned (2:1) to receive one intramuscular injection of BNT162b2 (interventional group) or maintain observation (control group). The randomization list was centrally generated with the SAS software for Windows. The randomization list was imported into the secure Research Electronic Data Capture platform (REDCap) used for the study electronic case report form (eCRF).”
Comment: Allocation sequence random. Allocation sequence concealed.
Imbalances in baseline characteristics appear to be compatible with chance.
|Deviations from intervention||
|Quote: "The study CombiVacS is a phase 2, non-blinded, adaptive, randomized, controlled, multicentre, clinical trial design.."
Per-protocol analysis was performed on the inmunological outcomes.
Reasons for exclusion were balanced between groups (withdrew consent: 1.3% vs 1.3%; protocol deviation: 0.7% vs 0.4%).
As we are assessing the effect of assignment to intervention (intent-to-treat effect), this domain was evaluated as some concerns for the immunogenicity outcomes: nAb GMT, sAb GMT, Cellular response.
|Missing outcome data||
Comment: 676 randomized; 663 analyzed for sAb GMT; 198 analyzed for sAB GMT; 151 analyzed for cellular response.
Data available for all or nearly all participants randomized for the outcome: sAb GMT
Data not available for all or nearly all participants randomized for the outcomes Cellular response, nAb GMT.
Reasons for missing data: Results collected from a random sample of participants.
Risk assessed to be some concerns for the outcomes: Cellular response, nAb GMT.
Risk assessed to be low for the outcome: sAb GMT
|Measurement of the outcome||
|Comment: Method of measuring the outcome probably appropriate. Measurement or ascertainment of outcome probably does not differ between groups.
Unblinded study (outcome assessor).
For immunogenicity outcomes, we consider that the assessment cannot possibly be influenced by knowledge of intervention assignment.
Risk assess to be low for the outcomes: nAb GMT, sAb GMT, Cellular response.
|Selection of the reported results||
|Comment: The prospective registry ( April 27, 2021)and retrospective protocol and statistical plan (May 21, 2021) were available. was available
Results were not selected from multiple outcome measurements or analyses of the data.
Trial analyzed as pre-specified.
Risk assessed to be low for the outcomes: nAb GMT, sAb GMT, Cellular response.
|Overall risk of bias||