Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Prevention of pressure ulcers
Systematic review	52 people Data from 1 RCT	Incidence of pressure ulcers 5 months with slab-foam cushions with bespoke contoured foam cushions Absolute results not reported	RR 1.06 95% CI 0.75 to 1.49 The confidence intervals of the RCTs included in the review suggest that they were probably underpowered to detect a clinically important difference between different cushions. 3 of the RCTs were of poor methodological quality (unclear method of randomisation/allocation concealment)		Not significant
Systematic review	141 people Data from 1 RCT	Incidence of pressure ulcers 3 months with gel-and-foam wheelchair cushion with foam cushion Absolute results not reported	RR 0.61 95% CI 0.37 to 1.00		Not significant
Systematic review	248 people Data from 1 RCT	Incidence of pressure ulcers 3 months with slab-foam cushions with contoured foam cushion Absolute results not reported	RR 1.00 95% CI 0.84 to 1.18		Not significant
Systematic review	32 people using wheelchairs Data from 1 RCT	Incidence of pressure ulcers with pressure-reducing seat cushion with foam cushions (3-inch convoluted [eggcrate] foam) Absolute results not reported	RR 0.68 95% CI 0.33 to 1.42		Not significant