The Performance of the Intubation Difficulty Scale among Obese Parturients Undergoing Cesarean Section

Table 4

The performance of the IDS among obese pregnant patients for detecting somewhat difficult intubation based on ROC curve analysis.

Cutoff point	Sensitivity (%)	Specificity (%)	PPV	NPV	LR+	LR−	AUC	Youden’s index
≥1	100	63.6	16.7	100	2.75	0	0.82	0.64
≥2	100	95.3	60.7	100	21.1	0	0.98	0.95
≥3	100	100	100	100	—	0	1.0	1.0
≥4	0	100	100	94.7	—	1.0	0.62	0

Note. PPV; positive predictive value, NPV; negative predictive value, LR+; positive likelihood ratio, LR−; negative likelihood ratio, AUC; area under the ROC curve, Youden’s index; = sensitivity + Specificity − 1 (its value ranges from 0 to 1; a value of 1 indicates that there are no false positives or false negatives; i.e., the test is perfect).