Foucher 1993.

Methods	RCT, part of a multicentre study, but outcomes from only 1 centre reported
Participants	69 OCTR, 128 OCTR with ligamentoplasty, 54 ECTR. In 2 cases ECTR was converted to OCTR No information given on age or sex of participants CTS was confirmed clinically and with EMG
Interventions	1‐portal ECTR (Agee) vs OCTR vs OCTR with ligamentoplasty
Outcomes	Up to 3 months follow‐up Grip strength, pain, days out of work
Notes	In French
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No information given
Allocation concealment (selection bias)	Unclear risk	No information given
Blinding of participants and personnel (performance bias) All outcomes	High risk	No information given. Participants and personnel could not be blinded
Blinding of outcome assessment (detection bias) All outcomes	High risk	No information given. Participants and personnel could not be blinded
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No information given
Selective reporting (reporting bias)	Unclear risk	No numerical data for most outcomes
Other bias	Unclear risk	No information given about baseline differences or financial support