Construction of a nomogram model to predict technical difficulty in performing laparoscopic sphincter-preserving radical resection for rectal cancer

Table 1 Scoring system for assessing difficulty of laparoscopic radical sphincter-preserving surgery for rectal cancer

Criteria	Score
Duration of postoperative hospital stay > 15 d	2
Surgical duration > 250 min	3
Intraoperative blood loss > 100 mL	1
Conversion to open surgery	3
Intraoperative use of trans-anal approach	2
Postoperative complications classified as CD grade II or above	1

The total score for the difficulty assessment is 12. A score ≥ 5 indicates a high-difficulty surgery, while a score < 5 indicates a low-difficulty surgery. CD: Clavien-Dindo.