Huang 2007.

Methods	Randomised controlled trial.
Participants	60 patients who underwent surgical removal of rectal cancer.
Interventions	Patients randomised to: ‐ Control: 6 cycles of post‐operative 5‐fluorouracil. ‐ Intervention: peri‐operative cimetidine (200mg qid orally for one week pre‐operatively, 400mg qid intravenously for one week post‐operatively followed by 200mg qid orally from day 8 post‐operatively till 2 years) plus 6 cycles of post‐operative 5‐fluorouracil.
Outcomes	5 year overall survival
Notes	Paper translated from Mandarin.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not mentioned.
Blinding (performance bias and detection bias) All outcomes	High risk	No placebo and hence unblinded. As treatments were given pre‐ and post‐operatively, this knowledge could have had an impact on the surgery that had taken place.
Incomplete outcome data (attrition bias) All outcomes	Low risk	States that all patients were followed‐up. Median follow‐up was 54 months.
Selective reporting (reporting bias)	High risk	In the methodology they state that the will use log‐rank to compare the survival rates. In the results they used chi‐squared methodology to compare survival rates at different points. It is unclear what the E (expected) survival value that was used at different time points (or how they derived them). It is also unclear if there was a chi squared correction performed (as there was only one degree of freedom (i.e.. two categories: cimetidine and control)).