Variable

Univariate analysis

Multivariate analysis

P value

P value

Odd ratio

Confidence interval 95%

Neck width

continuous

Categorical (>4 mm)

0.14

0.03*

0.18

1.6

0.85 - 3.49

Presence of IA

0.008*

0.04*

8.5

1.13 - 80.9