Potential bias	Authors' judgementa
Random sequence generation (selection bias)	High – not randomized or quasi‐randomized Unclear – states "randomized", but does not report method Low – describes method of randomization
Allocation concealment (selection bias)	High – not concealed, open‐label trial for individually randomized, method of concealment not adequate Unclear – details of method not reported or insufficient details Low – central allocation, sequentially numbered opaque sealed envelopes
Blinding (performance bias and detection bias)	High – personnel, participants or outcome assessors not blinded Unclear – no details reported, insufficient details reported Low – personnel, participants and outcome assessors blinded
Incomplete outcome data (attrition bias)	High – losses to follow‐up not evenly distributed across intervention and control group Unclear ‐ no details reported, insufficient details reported Low – losses to follow‐up evenly distributed across groups, reasons for loss to follow‐up and exclusions clearly stated
Selective reporting (reporting bias)	High – did not fully report measured or relevant outcomes Unclear – not enough information reported to judge Low – all stated outcomes reported
Other bias	High – other source of bias identified by review authors Low – no obvious other source of bias of concern to review authors
Adverse event monitoring (detection bias)	High – passive methods relying on spontaneous patient report only, undefined adverse events Unclear – not enough information reported to judge Low – key adverse events defined, prespecified active detection method
Incomplete adverse event reporting (reporting bias)	High – adverse event severity undefined, combination of treatment groups, post hoc cut‐offs for reporting adopted Unclear – not enough information reported to judge Low – clear reporting on important adverse events with numerical data by intervention group