Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Prevention of pressure ulcers
Systematic review	730 people over 18 years of age 2 RCTs in this analysis	Occurrence of pressure ulcers 35/373 (9%) with medical sheepskin overlay with or without usual care 80/365 (22%) with standard hospital mattress/usual care	RR 0.42 95% CI 0.22 to 0.81 P = 0.009	Moderate effect size	medical sheepskin overlay with or without usual care