Trial ChiCTR2000029765
Publication Wang D, Front Med (2021) (published paper)
Primary outcome on the report: Cure rate of the enrolled patients (defined as 1)fever attenuated for continuously 7 days, 2) twice COVD-19 nucleolus acid detections negative, 3) CT scan shows chest effusion absorbed more than 50% percent when the patient is discharged from hospita

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: "Randomization numbers were generated using SAS statistical software package (SAS Institute, Cary, USA). A computer- generated 1:1 block randomization scheme was used to assign patients to either treatment group or control one. Each consecutively coded patient was randomly enrolled by the sub-site investigators until the total number of cases allocated to the site was reached."
Allocation sequence random. Allocation concealment unclear.
Deviations from intervention
Some concerns 		Quote: "One case in the control group aggravated on day 3 after randomization was transferred to the tocilizumab group according to the rules of the study protocol."
Comment: Unblinded study (participants and personnel/carers).
Deviations from intended intervention arising because of the study context:
One participant cross-over.
No information on administration of any co-interventions of interest: antivirals, corticosteroids, biologics.
Hence, this domain was rated as some concern as not enough information on deviations that arose because of the trial context were reported.
Participants were not analyzed according to their randomized groups for the outcome.
Of note, 1 participant randomized to the control group was analyzed in the intervention group. Nevertheless, we considered the analysis to be probably appropriate to estimate the effect of assignment to intervention.
Risk assessed to be some concerns for outcome: Adverse events. Serious adverse events.
Missing outcome data
Low 		Comment: 65 participants randomized; 65 participants analyzed.
Data available for all or nearly all participants.
Risk assessed to be low for outcomes: Adverse events. Serious adverse events.
Measurement of the outcome
Some concerns 		Comment: Method of measuring the outcome probably appropriate.
Measurement or ascertainment of outcome probably does not differ between groups.
Unblinded study (outcome assessor).
The outcomes may contain both clinically- and laboratory-detected events. Assessment of these outcomes can be influenced by knowledge of the intervention assignment but is not likely in the context of a pandemic.
Risk assessed to be some concerns for the outcomes: Adverse events. Serious adverse events.
Selection of the reported results
Low 		Comment: The protocol, statistical analysis plan and registry were available.
Safety outcomes were pre-specified in the prospective protocol.
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 outcomes: Adverse events. Serious adverse events.
Overall risk of bias
Some concerns