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: “Using website software, enrolled patients were randomized in a 2:1 ratio to receive standard therapy alone, versus receiving standard therapy plus plasm of recovered COVID-19 individuals. Treatment allocation were assigned using randomized block design to provide symmetrically distributed base on key outcome-related characteristics”
Comment: Allocation sequence random. No information on allocation concealment. |
Deviations from intervention |
Some concerns |
Quote: “Plasma of recovered COVID-19 individuals was given and clinical data were monitored by the attending team, that was not aware of the research scheme. Radiological reports and laboratory parameter were registered by the administrative staff who was unaware of research protocol. The blood bank staff was blinded to group assignment. Patients were blinded to the intervention.”
Comment: Blinded study It is unclear how patients or attending teams could be blinded to transfusion or none. Deviations from intended intervention arising because of the study context: No participant cross-over. No information on administration of co-interventions of interest: biologics. Antivirals and corticosteroids were reported and balanced between groups. Hence, no information on whether deviations arose because of the trial context. This domain was rated as some concern as it is impossible to distinguish deviation because of trial context and deviation because of intervention effect. 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 some concerns for the outcomes: Incidence of viral negative conversion (D7). |
Missing outcome data |
Low |
Comment: 30 patients randomized; 30 patients analyzed.
Data available for all participants. Risk assessed to be low for the outcomes: Incidence of viral negative conversion (D7). |
Measurement of the outcome |
Low |
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: Incidence of viral negative conversion (D7). |
Selection of the reported results |
Some concerns |
Comment: The retrospective trial registry was available.
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: Incidence of viral negative conversion (D7). |
Overall risk of bias |
Some concerns |