2.3. Variables and outcomes
Age and sex of the patients, the type of disease (primary/recurrent), the number of orifices were recorded. The primary outcome of this study was the recurrence risk of the PSD after surgery. The secondary outcomes of the study were, the duration of surgery, the presence of short-term postoperative complication, and the patient outcomes that were studied included length of stay in the hospital and wound healing time between the surgical procedures. The duration of surgery was defined as the time interval from incision until the dressing is applied. The short-term postoperative complications were classified as present or absent for seven days postoperatively, and included seroma, wound site infection and abscess. We combined the complications as a new variable of having any type of this complication for using in regression models.