Table 2.

Linear regression models for 1- and 5-year VRR.

		1-year volume reduction ratio
		Univariate linear regression			Multivariate linear regression
		Beta	SE	p-value	Beta	SE	p-value
Age (years)		-0.002	0.002	0.15	//
Sex	Male	-0.07	0.05	0.21	//
Baseline volume (ml)		-0.003	0.002	0.06	-0.001	0.001	0.27
Nodule structure	PC	0.14	0.06	0.01	0.11	0.04	0.007
	PS	0.01	0.05	0.82	0.04	0.03	0.29
Nodule function	Non-AFTN	0.06	0.05	0.21	//
IAR		0.005	0.006	<0.001	0.004	0.0007	<0.001
		5-year volume reduction ratio
		Univariate linear regression			Multivariate linear regression
		Beta	SE	p-value	Beta	SE	p-value
Age (years)		-0.002	0.002	0.38	//
Sex	Male	0.02	0.07	0.72	//
Baseline volume (ml)		0.0001	0.002	0.95	//
Nodule structure	PC	0.09	0.07	0.18
	PS	0.02	0.06	0.80	//
Nodule function	Non-AFTN	0.03	0.06	0.64
IAR		0.005	0.001	<0.001	0.005	0.001	<0.001
Therapeutic efficacy	Yes	0.36	0.13	0.006	0.25	0.11	0.02

AFTN is for autonomously functioning thyroid nodules, PC is for predominantly cystic, and PS is for predominantly solid.