Tzovaras 2007.

Methods	Study: prospective randomised. Allocation: computer. Blinding: yes.
Participants	386 patients: 193 P / 193 C.
Interventions	Hernioplasty ATB: amoxicillin‐clavulanic 1,2 gr. MA: not standardised. Control: sterile saline.
Outcomes	IP= 5; IC= 9
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Code numbers generated by the Arcus Quiqstat randomisation program using numbered sealed envelopes.
Allocation concealment (selection bias)	Low risk	Quote: " The list with code numbers generated by the Arcus Quiqstat randomisation program was kept by a secretary, who was not involved in the treatment of the patients at any stage and was opened at the end of the trial for analysis of the results".
Blinding (performance bias and detection bias) All outcomes	Low risk	Yes
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Yes
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Yes