Table 5.

Sensitivity, specificity and predictive values of the risk score

	AUC (95%CI)	Cut-off value	S (%)	Sp (%)	PPV (%)	NPV (%)
Risk score*	0.78 (0.71–0.86)	> 3.5 points	80	65.1	43.5	90.7

* The points assigned to each predictor variable were based on coefficients obtained from the logistic-regression model adjusted for age, sex, alpha 1-antitripsin, cholesterol and neutrophils; S: sensitivity; Sp: specificity; PPV: positive predictive value; NPV: negative predictive value, AUC: area under the curve; CI: confidence interval