Figure 2.

Risk of bias assessment.

^aOnly blinding of outcome assessment evaluated; impossible to blind participants or personnel.

^bDowngraded due to post-randomisation exclusion of almost one-third of patients for lack of informed consent.

^cTerminated early due to slow recruitment, not data-driven.

^dDowngraded due to data-driven early termination for either apparent benefit (Girardis et al. ²² ) or harm (Barrot et al. ¹⁹ ).