Nomograms for pre- and postoperative prediction of long-term survival among proximal gastric cancer patients: A large-scale, single-center retrospective study

Table 4 Preoperative and postoperative nomograms accurately predicting overall survival in upper stomach cancer patients

	Training set		Validation set
	Preoperative nomogram	Postoperative nomogram	Preoperative nomogram	Postoperative nomogram
Area under the curve	0.811	0.799	0.821	0.774
Cutoff point	18	18	18	18
Sensitivity, %	0.736	0.706	0.768	0.855
Specificity, %	0.753	0.764	0.744	0.598
Positive predictive value, %	0.749	0.818	0.755	0.704
Negative predictive value, %	0.741	0.634	0.828	0.787
Positive likelihood ratio	2.98	2.99	3	2.127
Negative likelihood ratio	0.351	0.385	0.304	0.242