Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Adverse effects
[21] RCT	112 people In review [8]	Number of people with at least 1 device-related adverse effect 15/54 (28%) with 2-layer system 5/54 (9%) with 4-layer bandage	P = 0.01	Effect size not calculated	4-layer bandage
[20] RCT Crossover design	81 people	Adverse effects 4 weeks 67/135 (49.6%) with 2-layer compression 68/135 (50.4%) with 4-layer bandage	P value not reported