Table 2.

Diagnostic Validity Profile of Ultrasonographic Parameters in Predicting Difficult Intubation

Variable	EI (n = 985)	DI (n = 58)	OC	SE	SP	Accuracy % (95% CI)	OR (95% CI)	AUC	P value
TT (cm)	5.6 ± 0.2	6.1 ± 0.3	> 5.8	0.845	0.781	78.4 (75.8, 80.9)	1.06 (1.04, 1.07)	0.88	< 0.001
SH (cm)	1.3 ± 0.2	1.6 ± 0.2	> 1.4	0.81	0.852	85 (82.6, 87.1)	1.07 (1.06, 1.09)	0.898	< 0.001
ST (cm)	2.2 ± 0.2	2.5 ± 0.2	> 2.4	0.759	0.852	84.7 (82.3, 86.8)	1.1 (1.08, 1.12)	0.885	< 0.001
VH	142 (14.4)	42 (72.4)	-	0.724	0.856	84.9 (82.5, 87.0)	15.58 (8.52, 28.47)	0.79	< 0.001

Values are presented as mean ± SD or number (%). EI: easy intubation group, DI: difficult intubation group, OC: optimal criterion, SE: sensitivity, SP: specificity, OR: odds ratio, AUC: area under curve, TT: tongue thickness, SH: anterior neck soft tissue thickness from skin to hyoid bone, ST: anterior neck soft tissue thickness from skin to thyrohyoid membrane, VH: invisibility of hyoid bone. A P value < 0.05 was considered to be statistically significant.