Perioperative Intravenous Antibiotic Regimens and Surgical Site Infection After Colorectal Surgery: Clinical Associations and External Evaluation of Risk Prediction Models

Background/Objectives: Surgical site infection (SSI) remains a major complication after colorectal surgery. Comparative evidence for commonly used perioperative intravenous antibiotic regimens is limited, and risk prediction models require external evaluation before clinical use. We examined regimen–SSI associations and secondarily evaluated models using routine perioperative variables to distinguish patients with and without electronically recorded postoperative SSI.