Comparison 1. Foam surfaces compared with alternating pressure (active) air surfaces.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1.1 Proportion of participants developing a new pressure ulcer	4	2247	Risk Ratio (M‐H, Random, 95% CI)	1.59 [0.86, 2.95]
1.2 Time‐to‐pressure ulcer incidence	2		Hazard Ratio (IV, Random, 95% CI)	2.46 [0.61, 9.88]
1.3 Health‐related quality of life	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
1.3.1 90‐day EQ‐5D‐5L	1	267	Mean Difference (IV, Fixed, 95% CI)	0.00 [‐0.05, 0.05]
1.3.2 90‐day PU‐QoL‐UI	1	233	Mean Difference (IV, Fixed, 95% CI)	0.00 [‐0.03, 0.03]