Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Healing rates
[8] [9] Systematic review	120 older people with pressure ulcers in a nursing home, 101 completed study, grade 3 or 4 Data from 1 RCT	Complete ulcer healing 4 weeks 27/60 (45%) with water mattress 29/60 (48%) with layered-foam replacement mattress	RR 0.93 95% CI 0.63 to 1.37		Not significant