Cruz‐Korchin 1996.

Methods	CCT
Participants	Teaching Hospital, USA 20 patients (40 scars) Inclusion criteria: bilateral McKissock reduction mammaplasties Exclusion criteria: not stated Sex: all female Age: not stated
Interventions	Pre‐cut silicone elastomer sheet worn for 12 hours/day for 2 months (untreated adjacent scar on opposite breast of same patient used as control)
Outcomes	Length of follow‐up: measurements made at 2 months; follow‐up at 6 months Clinical: scar hypertrophy Complications: transient rash in 1 patient, minor skin maceration in 1 patient
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Quote: "Half the patients used the sheet on the breast that corresponded to her dominant hand and the other half used the sheet on their non dominant side”. Comment: no method of randomisation was used in the study
Allocation concealment (selection bias)	High risk	Comment: no method of allocation concealment was used in the study
Blinding of participants and personnel (performance bias) All outcomes	High risk	Comment: no further information is provided on blinding. Due to the nature of the treatment, we judged that participants and personnel could not be blinded.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Comment: no further information was given on blinding of outcome assessor which we judged to be at unclear risk of bias
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: 20 patients were enrolled in the study and table 2 in the results section gives outcomes for all 20 patients at 6 months follow up. Attrition bias was judged to be low risk.
Selective reporting (reporting bias)	Low risk	Comment: the study protocol was not sought, however all measurements discussed in the methods are reported in the results and clinically meaningful outcomes presented.
Other bias	Low risk	Comment: the study appears to be free of other sources of bias