Thorup 1985.

Study characteristics
Methods	RCT
Participants	50 people (from 13 years of age) undergoing inguinal hernia repair in Denmark between June and November 1983
Interventions	Group 1: hair removal with a razor (n = 24) Group 2: hair removal with depilatory cream (n = 26) Product details: the razors were disposable, the cream was Pilidan. Timing of hair removal: the day before surgery. Hair removed by: participants. Venue for hair removal: participants' own homes.
Outcomes	Primary outcome: participant preferences and efficiency of hair removal. Information was obtained from participants after hair removal but before surgery. Efficiency of hair removal was assessed on the operating table. No further details. Secondary outcome: wound infection assessed immediately postoperatively and on day of suture removal on day 10. No definition given for infection. No further details.
Notes	Paper published in Danish. No details of any funding. No details of conflict of interest.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "The patients were randomised" Comment: insufficient information provided about the sequence generation process.
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	Unclear risk	Not reported. Comment: unclear whether care providers were blinded to intervention allocation.
Blinding (performance bias and detection bias) Participants blinded	High risk	Not reported. Comment: not feasible due to nature of intervention ‐ use of cream was conducted by participants.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "The examinations on the day of operation and when the sutures were removed were carried out without any knowledge of the nature of depilation used." Comment: blinding of outcome assessment reported.
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	Low risk	Participants who dropped out are accounted for, and participants are distributed evenly across groups. Comment: the number of dropouts was judged to be unlikely to have altered the result, even in a worst‐case scenario (i.e. assuming that those that dropped out developed an SSI).
Selective reporting (reporting bias)	Low risk	Main outcomes reported. Comment: unlikely to be affected by reporting bias.
Other bias	Low risk	Comment: participant groups were equal or similar.