Schmidt 1981.

Study characteristics
Methods	This study was carried out in a secondary care setting. This study was blinded. Intention‐to‐treat analysis was not carried out. This study was conducted in Denmark.
Participants	60 participants were recruited: 5 dropped out. Inclusion criteria of the trial Adults Ordinary or refractory warts not specified Warts on the hands or feet
Interventions	5‐FU/SA Placebo (vehicle alone) Treatment was applied daily for 6 weeks.
Outcomes	Outcomes of the trial Cure (presumably at 6 weeks)
Notes	‐
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	This was described as randomised; no details were given.
Allocation concealment (selection bias)	Unclear risk	This was unclear; no details were given.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	This was unclear. This was described as double‐blind; the placebo appeared to be identical.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	This was unclear; no details were given.
Incomplete outcome data (attrition bias) All outcomes	High risk	5/60 participants completed. The results for 5 dropouts (2/30 Verrumal and 3/30 placebo) "could not be analysed" (page 1). No reasons were given. Also, it was not stated how many participants were randomised to each group – it was presumed that there were 30 in each group.
Selective reporting (reporting bias)	Low risk	All outcomes were reported.