Noble 2009.

Methods	ES followed by LC (Grp A) vs LCBDE during LC (Grp B). Randomised clinical trial. Sample size calculation: yes. Median length of follow‐up: 1.88 (IQR, 1.38 to 3.15) yrs.
Participants	Single centre. Southmead Hospital, Bristol, UK Higher‐risk pts: defined as being > 70 yrs age, > 60 with comorbidity, or > 50 with a BMI greater than 40. Pts with proven CBD stones on imaging or those with strong evidence of CBD stones (15 pts). Strong evidence of those with CBD stones was defined as those with a dilated CBD on transabdominal USS (5 mm in a 50‐yr old and 5+1 mm per decade) in addition to abnormal lLFTs. 2000 to 2006 Exclusion criteria: Pts with previous sphincterotomy, previous Bilroth II gastrectomy, pts unfit for general anaesthesia.
Interventions	Total of 91 pts. Group A ‐ 47 pts and Group B ‐ 44 pts.
Outcomes	Morbidity, bile duct clearance, conversion to open surgery, median postoperative stay.
Notes	If stones were confirmed on cholangiogram, sphincterotomy was performed and stones retrieved using balloon, basket, mechanical lithotripsy. During post‐ERCP LC, lap USS or cholangiography was performed. If stones were present, proceeded to LCBDE. LCBDE group: Transcystic/transcholedochal approach was decided by intra‐operative USS or cholangiogram. Choledochoscope was used.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation was by an independent computer‐generated random number system.
Allocation concealment (selection bias)	Unclear risk	Not described.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not possible.
Selective reporting (reporting bias)	Low risk	None.
Incomplete outcome data	Low risk	No missing data.
For‐profit bias	Low risk	Appears free of for‐profit support.
Other bias	Low risk	None.