Fig. 1

Calibration plots for severe complication on (A) POD1 and (B) POD3. A1) Patients aged < 70 years. A2) Patients aged ≥ 70 years. B1) Patients aged < 70 years. B2) Patients aged ≥ 70 years. Abbreviations: POD1 = postoperative day 1, POD3 = postoperative day 3