Rieder 1987.

Methods	Randomised, controlled Method of randomisation: draw system with sealed envelopes Type of shunt: ventriculoperitoneal shunts Location: London Follow‐up: 3 months Duration: 36 months
Participants	Inclusion: all children who presented for elective VP shunt insertion Exclusion: active infection or history of shunt infections. Immunosuppressed or receiving corticosteroid therapy. Allergy to penicillin or cephalothin Treatment: 32; control: 31
Interventions	25 mg/kg cephalothin IV before incision and 3 times postoperatively every 6 hours versus multivitamin preparation administration
Outcomes	Proportion of participants who had shunt infection No clear timing of outcome measurement described
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"Envelope draw system"
Allocation concealment (selection bias)	Low risk	"Pharmacist not otherwise involved in the patient's care"
Blinding of participants and personnel (performance bias) All outcomes	Low risk	The administered multivitamin sample in the control group has the same colour and is administered according to the same schedule as the cephalothin
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not described
Incomplete outcome data (attrition bias) All outcomes	Low risk	No apparent missing outcome data and dropouts described
Selective reporting (reporting bias)	Unclear risk	Pre‐specified outcome measures were unavailable
Other bias	Low risk	The study appears to be free of other sources of bias