Secondary outcomes

Time to onset of sacral HAPI in days up to 14 daysSacral HAPI incidence rates per 1000 bed daysSeverity of sacral HAPI up to 14 days, i.e. depth of tissue damage assessed using an internationally and nationally recognised classification system [Cost-effectiveness (an additional 14 days, up to 28 days): via an economic evaluation to compare the healthcare costs of prevention (using the prophylactic sacral dressings in addition to routine care compared to routine care alone) and benefits of prevention in terms of any difference in either incidence or treatment costs of sacral HAPIProcess (implementation) evaluation to determine intervention fidelity will allow a better understanding of the hospital contexts in which the trial was implemented. A process evaluation will identify contextual factors and co-interventions related to hospital procedures or individual clinical practice that may operate concurrently with the intervention. Fidelity will assess whether the delivery of the intervention to participants as outlined in the SOP and training processes is consistent (via quantitative monitoring and assessment methods) and explored (via qualitative methods)