Hendry 2010

Methods	Randomised trial comparing carbohydrate drink the evening before surgery and 30 days postoperative oral supplements to regular eating in patients undergoing hepatic resections for liver tumors. Geographical location Scotland and the Netherlands. Paper published 2010.
Participants	Inclusion criteria: Resectable benign or malignant liver tumor, age 18‐80, BMI 18‐30 scheduled for surgery between July 2006 and June 2008. Exclusion criteria: Pre‐existing conditions limiting mobility, underlying cirrhosis, history of liver resection, need for bile duct excision, need for central or extended hepatectomy.
Interventions	Intervention group received 400 ml commercial loading drink (Nutricia Preop®) 10 PM/4AM preop; 400 ml commerical supplement (Nutricia Fortisip®) bid postop (for one month). Control group received regular diet.
Outcomes	Primary outcome was time to passage of stool; secondary outcomes included mortality, postoperative complications. duration of hospitalization, rehospitalizations, and reoperations
Category of study	Supplements/Surgical.
Sample size calculation	Yes, but powered to see difference in time of appearance of stool.
Full paper or abstract only	Full paper.
Notes	Trial had factorial design in which patients also randomised to receiving or not receiving laxative (magnesium oxide) during hospitalization; data in paper presented only for combination groups (supplements versus no supplements and laxative versus no laxative). E‐mail request for further information sent to Dr Hendry on 2/17/12 at paul.hendry@ed.ac.uk., but no further information has been received as of March 20, 2012.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Block randomisation with random number table.
Allocation concealment (selection bias)	Low risk	Sealed opaque envelopes (not noted if serially numbered, but accepted as adequate concealment of allocation).
Blinding (performance bias and detection bias) All outcomes	High risk	Not blinded.
Incomplete outcome data (attrition bias) All outcomes	High risk	6/74 patients dropped out of trial by investigators because the planned resection could not be accomplished and palliative surgery done instead; no indication how many from each group. However, given the block design and the fact that 30 treated versus 38 control patients were compared, it is likely that most, or even all, came from treatment arm (which may have resulted in the removal of higher risk patients).
Selective reporting (reporting bias)	Low risk	Mortality and morbidity reported, but data presented for individuals who also did, or did not, receive laxatives postoperatively.
Other bias	Unclear risk	Unclear funder although commercial company provided the nutrient solutions.
Intent to treat analysis	High risk	Unknown from which arm each dropout came, so intent to treat analysis could not be done.
Baseline imbalance?	Low risk	No differences in baseline characteristics of the per protocol arms.
Early stopping?	Low risk	Sample size calculation indicated need for 14 patients for each of the four arms, and more than that reported.