Randomised controlled trials (RCTs) that evaluated TNP in patients aged over 18 years with any type of wound in any setting were eligible for inclusion if they assessed wound healing as a primary outcome. Acceptable measures of wound healing were time to complete healing, change in wound surface area, proportion of wounds healed, survival of split-thickness skin grafts and wound condition ready for surgery or skin grafting. Secondary outcomes were infection, pain, quality of life, oedema, microcirculation, bacterial load, adverse events and duration of hospital stay.
Included studies examined mixed chronic and acute wounds, diabetic wounds, pressure ulcers, skin grafts and acute wounds. Where reported, negative pressure ranged from 100 to 150 mm Hg with most studies using 125 mm Hg. A variety of dressings, gels and and other agents were employed as control interventions.
Two reviewers independently assessed the papers for inclusion at each stage, with disagreements resolved through discussion.