RCTComparison of the Effectiveness in Prevention of Hypertrophic Scars or Keloids Between Silicone Sheet, Silicone Gel and Paper Steri-strip-A Randomised Controlled Trial.

Patients who undergo gynecological surgery with transverse lower abdominal wounds and who undergo cardiovascular surgery with median sternotomy wounds in our hospital will be assessed. Those who have or will have diabetes, chemotherapy, radiotherapy and known history of allergy to silicone will be excluded. Altogether, about 75 patients will be recruited. Each patient's wound will be divided into two halves. One test dressing will be applied to a half, which is determined by random, and a different test dressing to the other half. The total 75 patients will thus be divided into 3 groups of 25 patients. One group will act to compare the effectiveness between silicone gel and silicone sheet, the second group between silicone sheet and paper tape, and the third group between silicone gel and paper tape. The dressings will be applied one week after surgery and at least 12 hours per day until 3 months after surgery. All patients will be followed up at 4 weeks, 8 weeks, 12 weeks, 6 months and 12 months. Three domains of outcomes will be measured. One is the appearance of the scars which will be rated with Vancouver scale, which has been proved to be a reliable scale.34 35 When rating with the Vancouver scale, standardised photographs of the scars will be taken in a standardised photo studio using a single high-resolution digital camera in a standardised light condition and at a fixed distance because any difference in photographic conditions will make difference in the Vancouver scores. The other two domains are pain and itching of the scars, which will be evaluated with Visual Analog Ratings (VAR). Pain and itching are very subjective, so the rating method should be very easy to understand and applicable for our patients and that is why we chose VAR as a tool.