| Bias | Author's judgement | Support for judgement |
| Randomization |
Low |
Quote: "This open-label, randomized clinical trial was designed to evaluate
the efficacy and safety of IFN β-1b in the treatment of patients with CoVID-19" "Patients were randomly recruited (1:1) to the IFN group or the control group. The method of randomization was the permuted block randomization (6 patients per block) "A biostatistician who was not involved in patients’ care did this process" Comment: Allocation sequence random. Allocation sequence concealed. |
| Deviations from intervention |
Some concerns |
Comment: Unblinded study.
No participant cross-over. No information on co-interventions of interest, biologics. Administration of antivirals and corticosteroids were reported. Appropriate analysis was used; participants analyzed according to their assigned intervention. |
| Missing outcome data |
Low |
Quote: "A total of 97 patients were screened. Of them, 15 patients did not
have the eligibility criteria of study and 2 patients were referred from
another hospital. Three and four patients withdrew the consent during the study in the IFN group and control groups, respectively. Four patients did not adhere to IFN injection after second or third dose. Also three patients in the control group were enrolled in another trial. Finally, 33 patients in each group completed the study" Comment: 80 eligible patients randomized, 66 analyzed. Missingness due to withdrawal of consent and dosage amounts (eligibility criteria) were unrelated to the outcome. Missingness due to transfer to another trial could have been due to the true value as this only occurred in the control group. However, this accounted for <5% of missing data. Risk assessed to be low for outcomes: Mortality. Time to clinical improvement. WHO score 6 and above. WHO score 7 and above. |
| Measurement of the outcome |
Some concerns |
Comment: Unblinded study.
Mortality is an observer-reported outcome not involving judgement. For WHO score 7 and above, we consider that the assessment cannot possibly be influenced by knowledge of intervention assignment. Risk assessed to be low for the outcome: Mortality. Incidence of WHO score 7 and above. Clinical improvement (defined as at least 2 points improvement on a 6-category scale) and WHO score 6 and above requires clinical judgment and could be affected by knowledge of intervention receipt, but are not likely in the context of the pandemic. Risk assessed to be some concerns for the outcomes: Time to clinical improvement. WHO score 6 and above. |
| Selection of the reported results |
Some concerns |
Comment: Neither the protocol nor the statistical analysis plan was available, though the authors stated they will include them as supplementary material. The registry was available and utilized.
No information on Time to clinical improvement was registered but it was reported as an outcome in the paper. Mortality, WHO score 6 and above and WHO score 7 and above outcomes were taken from the "Clinical outcome" endpoint that was registered and then reported in the paper as "Clinical status". However, the timepoints do not correspond. In the registry it is "end of treatment" and in the paper it is "at day 7, 14 and 28". 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 clinical improvement. Mortality. WHO score 6 and above. WHO score 7 and above. |
| Overall risk of bias |
Some concerns |