Table 4. Multivariate Analysis of Factors Associated with Mediastinal Metastasis.

Variables	Odds ratio (95% CI)	p value
Gender (male)	2.774 (1.445-5.324)	0.002
Primary tumor
Tumour size (>1 cm vs. ≤1 cm)	5.594 (1.929-16.223)	0.002
Extrathyroidal extension	0.997 (0.370-2.684)	0.994
Psammomatous calcification	0.903 (0.451-1.808)	0.773
Multifocality	1.525 (0.595-3.910)	0.38
Bilaterality	1.109 (0.439-2.800)	0.827
Nodal status
Central node metastasis (except RPELN metastasis)	1.321 (0.448-3.894)	0.614
RPELN metastasis	2.388 (1.111-5.131)	0.026

RPELN, right para-oesophageal lymph node.