Irwin 1995.

Methods	Study design: parallel RCT Study duration: not reported Study follow‐up: 48 h post‐operatively
Participants	Country: Hong Kong Setting: single centre Inclusion criteria: males undergoing elective minor orthopaedic surgery Number: treatment group (11); control group (10) Mean age ± SD (years): treatment group (45.6±19.0); control group (33.5±9.5) Sex (M/F): not reported Exclusion criteria: patients with respiratory, cardiac, hepatic or kidney insufficiency; history of peptic ulcer disease or allergy to aspirin, diclofenac or other prostaglandin inhibiting compounds
Interventions	Treatment group Diclofenac: 100 mg suppository before surgery then 100 mg at 8am on day 1 Control group Placebo: suppository before surgery and at 8am on day 1
Outcomes	Pre‐operative and post‐operative (at 24 h and 48 h) measurements of CrCl, urine output, sodium output, potassium output, fractional excretion of sodium, fractional excretion of potassium
Notes	Funding source: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Study was described as randomised, method of randomisation was not reported
Allocation concealment (selection bias)	Unclear risk	Insufficient information to permit judgement
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Insufficient information to permit judgement
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Insufficient information to permit judgement
Incomplete outcome data (attrition bias) All outcomes	Low risk	One patient withdrew from study; reason for missing outcome data unlikely to be related to outcome
Selective reporting (reporting bias)	Low risk	Study protocol matches outcomes presented
Other bias	Unclear risk	Insufficient information to permit judgement