Suc 1998.

Methods	Randomised clinical trial. Open cholecystectomy +/‐ ECD versus ERCP/ES. Cholecystectomy not necessarily performed in ERCP group. Multicentre. Exclusions ‐ none listed. Protocol violations ‐ 9, all withdrawn. Other withdrawals ‐ 9, due to incorrect diagnosis (malignant biliary obstruction). Sample size calculations: yes. Power analysis based on primary outcome variable of additional procedures required, with 95 pts per group required with a power of 90% at the 0.05 level.
Participants	France. Commenced September 1989 and completed September 1994. 220 consecutive adult pts randomised. Inclusion criteria: Adult (> 18 yrs). One of: jaundice, mild AP, mild cholangitis, biliary colic + raised ALP, CDS or dilated CD on USS. Exclusion criteria: Cholecystitis (thick gallbladder wall on USS). No stones on USS and CBD < 1 cm. Pts unable to have ERCP (previous total or B2 gastrectomy, or choledochoenterostomy).
Interventions	All cholecystectomies by surgeons, all ERCPs by gastroenterologists. Surgical group: OC (if not performed previously ‐ 3 pts). CBDE +/‐ choledochoscopy. Duct closure either primary, +/‐ T‐tube, or choledochoenterostomy. Endoscopic group: ERCP and cholangiogram. Basket extraction of stones OC subsequently only if cholecystitis or cholangitis developed.
Outcomes	Retained stones, additional procedures, mortality, morbidity, total duration of hospital stay.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Random number tables.
Allocation concealment (selection bias)	Low risk	Telephone call to co‐ordinating centre.
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.