Table 2.

Univariate and multivariate logistic regression analysis of factors associated with extrathyroidal extension in patients with PTC

Variable	Extrathyroidal extension (all)						Advanced extrathyroidal extension (T4 stage)
	univariate			multivariate			univariate			multivariate
	OR	95% CI	p value	OR	95% CI	p value	OR	95% CI	p value	OR	95% CI	p value
Age	1.025	1.014–1.037	<0.001	1.031	1.019–1.044	<0.001	1.042	1.022–1.063	<0.001	1.046	1.025–1.067	<0.001
Sex	0.727	0.510–1.037	0.078				0.775	0.409–1.469	0.435
BMI	1.094	1.055–1.135	<0.001	1.074	1.032–1.117	<0.001	1.114	1.050–1.183	<0.001	1.081	1.010–1.156	0.024
Tumor size	1.758	1.545–2.001	<0.001	1.847	1.614–2.114	<0.001	1.915	1.588–2.309	<0.001	2.052	1.668–2.523	<0.001
Hashimoto's thyroiditis	1.110	0.760–1.622	0.590				0.363	0.129–1.017	0.054

The total number of patients was 887.