Trial NCT04333368, EudraCT 2020-001287-28
Publication Monsel A, Crit Care (2022) (published paper)
Primary outcome on the report: Respiratory improvement assessed as the partial pressure of oxygen to fractional inspired oxygen (PaO2/FiO2)-ratio change between baseline (D0) and D7 post-randomization.

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: “Randomization and data collection were centralised using a web-based electronic case-report form (Cleanweb Telemedicine Technologies™) on a sponsor-operated secure server. To maintain blinding of the investigators and clinicians, conditioning, labelling and distributions of UC-MSCs and placebo pouches were rigorously identical, with both being pre-conditioned in opaque bags [protocol]." nt: Allocation sequence random
Allocation sequence concealed
Deviations from intervention
Low 		Quote: “All healthcare providers and patients were unaware of treatment assignment”
Comment: Blinded study (participants and personnel/carers)
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: Mortality (D28). Time to death. Adverse events. Serious adverse events.
Missing outcome data
Low 		Comment: 47 participants randomized; 45 participants analyzed.
Data available for all or nearly all participants randomized.
Risk assessed to be low for the outcomes: Mortality (D28). Time to death. 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: Mortality (D28). Time to death. Adverse events. Serious adverse events.
Selection of the reported results
Low 		Comment: The protocol, statistical analysis plan, registry were available (dated April 3, 2020).
Outcome pre-specified.
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 outcome: Mortality (D28). Time to death. Adverse events. Serious adverse events.
Overall risk of bias
Low