Oteiza 2004.

Methods	Study: prospective, randomised. Allocation: computer. Blinding: yes.
Participants	247 patients: 124 P / 123 C.
Interventions	Hernioplasty ATB: amoxicillin‐clavulanic 2 gr IV. MA: 15‐30 minutes before the incision. Control: no treatment.
Outcomes	IP= 1; IC= 0
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer generated list.
Allocation concealment (selection bias)	High risk	Information not provided. Comment: Probably not done.
Blinding (performance bias and detection bias) All outcomes	High risk	Information not provided. Comment: Probably not done.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Information not provided. Comment: Probably not done.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Not mentioned. Comment: Probably not done.