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: “A web-based randomization system used to assign a randomization code for each patient. Investigator at the investigational site was able to enter the web-based randomization system specific to the study through assigned username and password. After entering patient-related information (patient number, date of birth, patient initials), the system provided randomization code for the future use by investigators” (preprint) Comment: Allocation sequence random. Allocation sequence concealed. |
| Deviations from intervention |
Low |
Comment: Study reported as "open label", however, they used placebo in the control group and patients and clinical staff were blinded to the treatment allocation. Quote: "Except the investigator, all other clinical staff involved in the daily surveying of the study participants blinded to whether the patients were receiving placebo or active. The patients were also unaware if they were receiving active or placebo."
Unclear blinding (participants and personnel/carers) Deviations from intended intervention arising because of the study context: No participant cross-over. In the outpatient setting, we consider no important cointerventions of interest. Hence, no deviation arose because of the trial context. Our analysis for the binary outcome is an 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: 93 participants randomized; 93 participants analyzed.
Data available for all randomized participants. Risk assessed to be low for the outcomes: Adverse events. Serious adverse events. |
| Measurement of the outcome |
Some concerns |
Comment: Placebo controlled study, yet reported as open label.
Method of measuring the outcome probably appropriate. Measurement or ascertainment of outcome probably does not differ between groups. Unclear blinding (outcome assessor). The authors reported on adverse events and serious adverse events that may contain both clinically- and laboratory-detected events, which can be influenced by knowledge of the intervention assignment, but is not likely in the context of the pandemic. Risk assessed to be some concerns for the outcomes: Adverse events. Serious adverse events. |
| Selection of the reported results |
Some concerns |
Comment: Neither the protocol nor the statistical analysis plan was available. The registry was available but retrospective (dated October 2020).
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 outcome: Adverse events. Serious adverse events. |
| Overall risk of bias |
Some concerns |