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 |
Report: "Patients were randomly assigned using a computer-generated randomization sequence, with balanced permuted blocks of two. The sequence was prepared centrally at the Data Center. Both treatment and placebo were concealed
using opaque bags and tape to cover the infusion line."
Protocol: “The randomization of participating subjects will be conducted by the person in charge of randomizing the study using an electronic system. Only the person responsible for randomization and the physician in the Transfusion Medicine Central Team administering treatment will know the product administered to each patient (unblind). Neither the patient nor the researchers will have knowledge of the administered treatment, conducting a double-blind study. The unblind team will keep a record of the product assignments and their administrations that will be kept confidential.” Comment: Allocation sequence random. Allocation sequence concealed. |
| Deviations from intervention |
Low |
Quote: “A randomized, double-blind, placebo-controlled study. Neither the patient nor the researchers will have knowledge of the administered treatment”.
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: Adverse events. Serious adverse events. |
| Missing outcome data |
Low |
Comment: 160 participants randomized; 160 participants analyzed.
Data available for all participants. Risk assessed to be low for the outcomes: Adverse events. Serious adverse events. |
| 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: Adverse events. Serious adverse events. |
| Selection of the reported results |
Some concerns |
Comment: The protocol, statistical analysis plan and registry were available but very retrospective.
No information on whether the result was selected from multiple outcome measurements or analyses of the data. No information on whether the trial was analyzed as pre-specified. Risk assessed to be some concerns for the outcomes: Adverse events. Serious adverse events |
| Overall risk of bias |
Some concerns |