Table 4.

Sensitivity/ Specificity/ Positive Predictive Value / Negative Predictive Value and p value of continuous variables with cut off values and categorical variables

S.No	Parameter (cut off)	Sensitivity %	Specificity%	PPV%	NPV%	p value
1.	The Facial recess width (4.2 mm)	89.5	68.8	64	91.7	< 0.001
2.	Location to mastoid segment (2 mm)	89.5	53.1	53.1	89.5	0.002
3.	Basal turn and ICA angle (3.5 degrees)	89.5	40.6	47.2	86.7	0.311
4.	Angle between EAC and Basal turn (13.5 degrees)	78.9	53.1	50	80.9	0.019
5.	Anterior border of IAC (174 degrees)	68.4	37.5	39.3	66.7	0.690
6.	IAC to sagittal plane angle (87 degrees)	68.4	34.8	38.2	64.7	0.572
7.	Jugular Bulb	73.7	21.9	35.9	58.3	0.743
8.	Sigmoid sinus line	52.6	59.4	43.4	67.8	0.405
9.	Prediction line	26.3	93.8	71.4	93.7	0.087

ICA: Internal Carotid Artery EAC: External Auditory Canal