Fig. 1.

Characteristics of the selected studies

a Number of articles published per year on the topic. b Distribution of the selected studies according to the types of digestive surgery. c Selected endpoints and their frequency. d Distribution of the values of the area under the curve for the reported machine-learning models that aimed to predict postoperative complications after digestive surgery. GI, gastrointestinal; POC, postoperative complications; PE, pulmonary embolism; VTE, venous thromboembolism; POPF, postoperative pancreatic fistula; AL, anastomotic leakage; SSI, surgical site infection; AUC, area under the curve.