Andersson 2003.

Methods	Randomised clinical trial.
Participants	Country: Sweden. Number randomised: 20. Mean age: 39 years. Females: 14 (70%). Inclusion criteria: ASA I Requires laparoscopic cholecystectomy.
Interventions	Participants were randomly assigned to two groups: Group 1: abdominal wall lift (n = 10). Group 2: pneumoperitoneum with 11 to 13 mm Hg pressure (n = 10). Device used for abdominal lift: intra‐peritoneal device.
Outcomes	The outcome measure was operating time.
Notes	One cross‐over participant from abdominal wall lift group to control due to poor visualisation. Attempts were made to contact the author in February 2007.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Comment: This information was not available.
Allocation concealment (selection bias)	Unclear risk	Comment: This information was not available.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Comment: This information was not available.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Comment: This information was not available.
Incomplete outcome data (attrition bias) All outcomes	High risk	Comment: There were post‐randomisation drop‐outs.
Selective reporting (reporting bias)	High risk	Comment: Important outcomes were not reported.
Vested interest bias	Unclear risk	Quote: "This study was supported by Karolinska Institute." Comment: Not clear whether this was the only source of support.