Ahn 1989.
| Methods | RCT | |
| Participants | Setting unclear ‐ the authors have affiliations with academic institutions in USA and Korea 10 patients (14 scars) Inclusion criteria: hypertrophic scars Exclusion criteria: not stated Sex: not stated Age: 19 to 78 years | |
| Interventions | silicone gel sheeting applied to 14 scars for at least 12 hours per day over 8 weeks (untreated adjacent or mirror image scars on same patients used as control) | |
| Outcomes | Length of follow‐up: measurements at 4, 8 and 12 weeks Clinical: scar elasticity, scar appearance, foreign body reaction Complications: occasional transient rashes or superficial maceration, both of which resolved promptly when treatment withdrawn | |
| Notes | Scars were photographed and biopsy specimens taken Elasticity quantitated serially with the use of an elastometer | |
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Unclear risk | Comment: no information is provided on random sequence generation which we judged to be at unclear risk of bias. |
| Allocation concealment (selection bias) | Unclear risk | Comment: no information is provided on the allocation concealment which we judged to be at unclear risk of bias. |
| Blinding of participants and personnel (performance bias) All outcomes | High risk | Quote: "a 6 x 7cm test area of scar was selected so that an untreated control area was available". Comment: due to the nature of the intervention it was judged that participants and personnel could not be blinded |
| Blinding of outcome assessment (detection bias) All outcomes | Unclear risk | Comment: no information is provided on the blinding of outcome assessor which we judged to be at unclear risk of bias |
| Incomplete outcome data (attrition bias) All outcomes | Low risk | Quote: "silicone gel sheets were applied to 14 hypertrophic scars in 10 adults". Comment: results for all 14 scars are presented in table 1. There was no loss to follow‐up. |
| 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 free of other sources of bias. Scars (not people) were the unit of analysis. |