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: “Patients were randomized 4:1 to convalescent or standard plasma using permuted block randomization lists generated using SAS software, and implemented using an interactive web response randomization tool in REDCap.”
Comment: Allocation sequence random. Allocation sequence concealed. |
Deviations from intervention |
Low |
Quote: “Study members, who were unblinded, randomized subjects as above. The only other individuals who were unblinded were Blood Bank personnel since they needed to label and dispense the masked CP or SP. The bags of CP or SP had an identical label, stating “CP or SP” to preserve blinding.” (publication)
"Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)" (registry) Comment: Blinded study (participants and personnel/carers) Data for the outcome were analyzed using intention-to-treat analysis. This method was considered appropriate to estimate the effect of assignment to intervention. Risk assessed to be low for the outcomes: Mortality (D28). Mortality (D60 or more). Time to death. Clinical improvement (D28). Time to clinical improvement. Serious adverse events. Adverse events. |
Missing outcome data |
Low |
Comment: 74 participants randomized; 74 participants analyzed.
Data available for all participants randomized. Risk assessed to be low for the outcomes: Mortality (D28). Mortality (D60 or more). Time to death. Clinical improvement (D28). Time to clinical improvement. Adverse events. Serious adverse events. |
Measurement of the outcome |
Low |
Quote: “All study personnel who collected data were blinded to study assignment at all times”).
Comment: Method of measuring the outcome probably appropriate. Measurement or ascertainment of outcome does not differ between groups. Blinded study (outcome assessor) Risk assessed to be low for the outcomes: Mortality (D28). Mortality (D60 or more). Time to death. Clinical improvement (D28). Time to clinical improvement. Adverse events. Serious adverse events. |
Selection of the reported results |
Some concerns |
Comment: The prospective registry was available (dated April 13th, 2020)
MORTALITY (D60 or more) Outcome pre-specified. 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 outcome: Mortality (D60 or more). MORTALITY (D28) Outcome was not pre-specified, however, we do not consider the reporting of this outcome to be selective since mortality should be reported even if not planned. Results were probably not selected from multiple outcome measurements or analyses of the data. Trial analyzed as pre-specified. Risk assessed to be low for the outcome: Mortality (D28). TIME TO DEATH, CLINICAL IMPROVEMENT, TIME TO CLINICAL IMPROVEMENT, ADVERSE and SERIOUS ADVERSE EVENTS Outcomes not pre-specified in the registry. No information on whether the result was selected from multiple outcome measurements or analyses of the data. Trial probably not analyzed as pre-specified. Risk assessed to be some concerns for the outcomes: Time to death. Clinical improvement (D28). Time to clinical improvement. Adverse events. Serious adverse events. |
Overall risk of bias |
Some concerns |