Grober 2013.

Study characteristics
Methods	RCT
Participants	215 adult men having surgery involving their genitalia in Canada (dates not given). Included vasectomy reversal, penile prosthesis insertion, testis biopsy, orchidectomy, and scrotal skin surgery.
Interventions	Group 1: hair removal with clippers (n = 107) Group 2: hair removal with razor (n = 108) Product details: razors were Gillette 2 blade disposable, clippers were 3M surgical clippers. Timing of hair removal: after anaesthesia had commenced. Hair removed by: not specified. Venue for hair removal: the operating department.
Outcomes	Primary outcome: effectiveness of method and skin trauma. Photographs taken immediately after hair removal and assessed in a blinded fashion by "groups of urologic surgeons and surgical nursing staff". Secondary outcome: SSIs defined by evidence of increasing cellulitis or pus, or both, within 3 months of surgery, monitored throughout the duration of study. Participants assessed at 1‐ and 3‐month follow‐up visits, no details regarding who performed the assessment.
Notes	No funding sources mentioned. Conflict of interest status: none declared.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "subjects were randomised" Comment: method used for random sequence generation not reported.
Allocation concealment (selection bias)	Unclear risk	Not reported. Comment: not clear whether the person responsible for allocation to groups would have been able to predict to which group a potential participant would be allocated.
Blinding (performance bias and detection bias) Care providers blinded	High risk	Quote: "Members of the surgical team ... perform the hair removal on the scrotal skin within the surgical field ..." Comment: care providers were involved in hair removal.
Blinding (performance bias and detection bias) Participants blinded	High risk	Quote: "Participants not blinded" Comment: it is possible that participants were aware of allocation.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "photographs were reviewed in a blinded fashion" Comment: assessors were blinded to intervention.
Incomplete outcome data (attrition bias) ITT analysis undertaken	Unclear risk	Not reported. Comment: no discussion of whether participants were analysed in the groups to which they had been allocated.
Incomplete outcome data (attrition bias) Drop out rate acceptable	Unclear risk	Not reported. Comment: insufficient details to permit a judgement.
Selective reporting (reporting bias)	Low risk	Main outcomes reported. Comment: unlikely to be affected by reporting bias.
Other bias	Unclear risk	Comment: no information on the similarity of groups.