Population
Patients undergoing gastric cancer surgery (n= 999).
Intervention
Nomogram of preoperative variables to predict intraoperative blood transfusion (primary cohort, n= 666).
Comparison
Nomogram of preoperative variables to predict intraoperative blood transfusion (validation cohort, n= 333).
Outcome
The following risk factors for transfusion were identified and used to construct the nomogram: ASA (American Society of Anaesthesiologists) physical status, comorbidities, tumour location, Clinical Tumour-Lymph Node-Metastasis stage, and a preoperative haemoglobin level less than 80 g/L. The concordance index was 0.859 and 0.850 in the primary and validation cohorts, respectively, which both indicated good discrimination of the nomogram. Additionally, both calibration curves and Hosmer-Lemeshow tests demonstrated high agreement between the predictions and actual outcomes.