Lella 2006.

Methods	Parallel randomised controlled clinical trial Randomisation ratio: superiority design
Participants	120 patients with cholecysto‐choledocholithiasis detected by transabdominal ultrasound and magnetic resonance cholangiopancreatography (MRCP); mean age 54.2 years, male 43%; history of relapsing pancreatitis: 30%; bile duct diameter < 8 mm: 12.5% Inclusion criteria: gallbladder and main bile duct stones and one or more of the following patient‐related risk factors for post‐ERCP pancreatitis: age < 60 years;history of relapsing pancreatitis; bile duct diameter < 8 mm Exclusion criteria: chronic pancreatitis and previous sphincterotomy Diagnostic criteria: gallbladder and main bile duct stones detected by both transabdominal ultrasound and MRCP
Interventions	Number of study centres: one Treatment before study: not reported Type of interventions: 60 participants treated in a single step with videolaparoscopic cholecystectomy, intraoperative cholangiography, and endoscopic sphincterotomy during the surgical procedure with the rendezvous technique versus 60 treated with preoperative ERCP and endoscopic sphincterotomy using a traditional method of bile duct cannulation
Outcomes	Rate of acute pancreatitis, level of amylasemia
Notes	Run‐in period: from January 2002 to September 2004 Study terminated before regular end (for benefit or because of adverse events): no Follow‐up: not reported Funding sources: no information reported Declaration of interest: no information reported Country: Italy
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated randomisation into two groups
Allocation concealment (selection bias)	Unclear risk	No report on concealment of randomisation
Blinding of participants and personnel (performance bias) All outcomes	High risk	Participants and personnel were not blinded.
Blinding of outcome assessment (detection bias) All outcomes	High risk	The outcomes assessors were not blinded.
Incomplete outcome data (attrition bias) All outcomes	High risk	in the LERV group "in one patient, the guidewire did not pass through the papilla, so it was necessary to make a precut. In two participants, conversion to open surgery with choledochotomy was needed: in one case due to prepapillary giant impacted stones and in the other case due to a technical problem (loss of the wire in the intestinal loops). The latter patient did not undergo the endoscopic procedure and was therefore excluded from the statistical analysis". In the other group (preoperative ERCP and endoscopic sphincterotomy performed using a traditional method of bile duct cannulation), the precut technique was needed in one patient.
Selective reporting (reporting bias)	Unclear risk	The trial protocol was not available.
Other bias	High risk	The learning curve was not reported.
for‐profit bias	Unclear risk	Information about sponsorship or trial support not reported