Fig. 3

The ROC curve for predicting high aspiration risk in patients with gastric cancer derived from tumor size, gastrointestinal obstruction, tumor located in cardia, tumor located in antrum, N3 stage, logistic regression predicted probability using the above five variables (tumor size, obstruction, tumor located in cardia, tumor located in antrum, N3 stage) and logistic regression predicted probability using the above four variables (tumor size, tumor located in cardia, tumor located in antrum and N3 stage). Area under ROC curve (AUC) were 0.687 (95% CI 0.615–0.759), 0.583 (95% CI 0.498–0.668), 0.391 (95% CI 0.321–0.462), 0.617 (95% CI 0.536–0.697), 0.617 (95% CI 0.536–0.697), 0.608 (95% CI 0.527–0.690), 0.835 (95% CI 0.780–0.890) and 0.798 (95% CI 0.739–0.857), respectively. CI = confidence interval