Ahmed 1987.

Methods	Randomised controlled trial. Randomisation method not stated. Double‐blinded. Unclear blinding of outcome assessor.
Participants	190 patients enrolled in the study. Age‐range: Treatment group: 10‐45, Placebo group: 10‐40 Mean: Treatment group: 19,2 +/‐ 6,7 (s.d.), Placebo group: 21,3 +/‐ 8,7 (s.d.) Patients with normal, gangrenous or perforated appendix and antibiotics prior to surgery were excluded before randomisation.
Interventions	Treatment group: Metronidazole 500 mg=100 ml i.v inter‐operatively. Placebo group: Saline 100 ml i.v peroperatively
Outcomes	Wound infection (Purulent discharge from the incision).
Notes	No drain treatment.
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment?	Unclear risk	B ‐ Unclear