Table 4.

Accuracy of the nomogram in predicting the risk of severe CAP at the optimal threshold value

Variable	Value (95%CI)
	Training set	Testing set
Accuracy	0.90 (0.88, 0.92)	0.89 (0.85, 0.93)
AUC	0.87 (0.83, 0.90)	0.84 (0.78, 0.90)
Sensitivity	0.90 (0.81, 0.95)	0.82 (0.66, 0.92)
Specificity	0.71 (0.67, 0.74)	0.71 (0.65, 0.76)
Positive predictive value	0.63 (0.41, 0.80)	0.57 (0.20, 0.88)
Negative predictive value	0.91 (0.88, 0.93)	0.90 (0.86, 0.93)
Positive likelihood ratio	13.63 (6.17, 30.11)	10.75 (2.51, 45.99)
Negative likelihood ratio	0.82 (0.74,0.91)	0.89 (0.79, 1.01)