Randomization and blinding
inter-sphincteric fistula
Randomization was performed the day before surgery. Patients were randomized using a computer-generated randomization code and assigned either to experimental Group I for high ligation of the inter-sphincteric fistula tract by lateral approach procedure or experimental Group II for fistulotomy and primary reconstruction of anal sphincter The two groups were balanced at a ratio of 1 : 1. The study was carried out under single-blind conditions.