Trial design {8}
death, silicone foam
This study is a multi-site, parallel group, superiority RCT comparing the effectiveness of a prophylactic silicone foam border dressing in preventing sacral HAPI in hospitalised patients assessed at risk for PI. The unit of randomisation is eligible consenting patients who receive either the prophylactic sacral dressing or the routine care alone. Randomised to either the dressing group or the routine care only group is via a computer-generated 1:1 ratio, in varying permuted block sizes of four, six, and eight, stratified by hospital and division (i.e. medical or surgical).All patients are followed for up to 14 days or until the trial endpoint, which is development of a new sacral HAPI, hospital discharge, or death—whichever occurs first. Patients who develop a HAPI in either arm are exited from the prevention trial and followed for an additional 14 days until discharge or death—whichever occurs first (up to a total of 28 days) to provide data on PI prevention and treatment costs. This will enable an extended economic evaluation that considers the benefits of prevention in terms of any reduced HAPI treatment costs or HLOS, alongside the costs of prevention.An integral part of this study is its process evaluation. Process evaluations are particularly important for multi-site trials where it is necessary to determine whether interventions are implemented and received consistently across sites and to understand differences between them [