Gioffrè Florio 1993.

Study characteristics
Methods	Study design: prospective randomised controlled trial Randomisation technique: random allocation Allocation concealment: not reported Inclusion criteria: well explained Exclusion criteria: well explained Lost to follow‐up: not mentioned Baseline variables: matching between both limbs of the trial Intention‐to‐treat analysis: not reported Sample size calculations (power of the study): not reported
Participants	Country: Italy Number of participants: FG: 12 and NFG: 12 Mean age: not reported
Interventions	FG: Tissucol® was applied under skin flaps following breast and axillary surgery Types of surgical intervention: modified radical mastectomy wide local excision axillary dissection Confounding interventions: drain insertion
Outcomes	Primary: incidence of seroma Secondary: mean seroma volume
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Participants were allocated randomly to both arms of the trial
Allocation concealment (selection bias)	High risk	Not reported
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not reported
Blinding of outcome assessment (detection bias) All outcomes	High risk	Not reported
Incomplete outcome data (attrition bias) All outcomes	High risk	Not reported
Selective reporting (reporting bias)	Low risk	No
Other bias	High risk	No reporting of conflict of interest