Larsen 2004.

Methods	Randomised clinical trial.
Participants	Country: Denmark. Number randomised: 50. Mean age: 49 years. Females: 18 (36%). Inclusion criteria: Elective participants > 18 years BMI of 30 or less. Exclusion criteria: Acute pancreatitis Cholecystitis Cholangitis Blood diseases Rheumatic diseases Acute infectious diseases Renal diseases Liver diseases.
Interventions	Participants were randomly assigned to two groups: Group 1: abdominal wall lift (n = 22). Group 2: pneumoperitoneum with 12 mm Hg pressure (n = 28). Device used for abdominal lift: subcutaneous device.
Outcomes	The main outcome measure was operating time.
Notes	Withdrawal = 4 because of technical problems with recording echocardiography (in this trial, echocardiographic changes were compared between the groups). Attempts were made to contact the author in February 2007.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "The allocation sequence was generated by random numbers".
Allocation concealment (selection bias)	Unclear risk	Quote: "Patients were allocated randomly by opening sealed envelopes on the day of operation." Comment: Further information was not available.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Quote: "The intervention assignments were unknown to the patients and the nursing staff." Comment: It was not clear whether the other healthcare providers were blinded.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Quote: "The intervention assignments were unknown to the patients and the nursing staff." Comment: It was not clear whether the other healthcare providers were blinded.
Incomplete outcome data (attrition bias) All outcomes	High risk	Comment: There were postrandomisation drop‐outs.
Selective reporting (reporting bias)	Low risk	Comment: All important outcomes were reported.
Vested interest bias	Unclear risk	Quote: "This study was supported by funding from Nordjyllands Amts Forskningsraad, Aalborg Stifts Julelotteri and Det Obelske Familefond." Comment: Not clear whether these were the only sources of support.