Clipping hair immediately before an operation has been associated with a lower risk of SSI than shaving or clipping the night before an operation. One study reported SSI rates were 5.6 percent using a razor compared to 0.6 percent using a depilatory, 3.1 percent shaving immediately before incision compared to 7.1 percent within 24 hours preoperatively and 1.8 percent clipping immediately before incision compared to 4.0 percent within 24 hours preoperatively. If shaving was performed more than 24 hours preoperatively, the SSI rate exceeded 20 percent.