3.

Univariate and multivariate logistic regression for CLNM

Independent variable	Univariate		Multivariate
Independent variable	OR (95% CI)	P	OR (95% CI)	P
^aThe P-value means the difference between the group multifocal lesion and solitary lesions. ^bThe P-value means the difference among the upper third, top third, lower third, and isthmus in group of solitary lesion.
Gender		0.000		0.000
Female	1 (reference)		1 (reference)
Male	1.832 (1.427–2.351)		1.845 (1.419–2.399)
Age, years		0.000		0.000
< 45	1 (reference)		1 (reference)
≥ 45	0.665 (0.537–0.824)		0.624 (0.498–0.782)
PTMC with HT		0.790
Yes	1 (reference)		-	-
No	0.966 (0.744–1.253)		-
Tumor size (> 6 mmvs. ≤ 6 mm)		0.000		0.000
≤ 6 mm	1 (reference)		1 (reference)
> 6 mm	2.529 (2.013–3.148)		2.137 (1.694–2.697)
Extrathyroidal extension		0.000		0.001
Yes	1 (reference)		1 (reference)
No	0.497 (0.391–0.632)		0.643 (0.498–0.782)
Multifocal		0.000^a		0.782
Yes	1 (reference)		1 (reference)
No	0.504 (0.406–0.627)		0.953 (0.679–1338)
Bilateralism		0.000		0.000
Yes	1 (reference)		1 (reference)
No	0.397 (0.312–0.504)		0.495 (0.343–0.715)
Subtype		0.017
Classical	1 (reference)		1 (reference)
Follicular variant	2.732 (1.253–5.957)	0.009	2.101 (0.932–4.738)	0.074
Hürthle cell variant	3.512 (0.585–21.098)	0.143	1.926 (0.298–12.440)	0.491
Solitary letion		0.049^b
Upper third	1 (reference)		-	-
Middle third	1.003 (0.681–1.478)	1.000	-
Lower third	1.495 (1.067–2.093)	0.023	-
Isthmus	5.675 (1.989–16.087)	0.003	-