Ultrasound Risk Categories for Thyroid Nodules and Cytology Results: A Single Institution’s Experience after the Adoption of the 2016 Update of Medical Guidelines by the American Association of Clinical Endocrinologists and Associazione Medici Endocrinologi

Table 2

The greater diameters of thyroid nodules evaluated by fine needle aspiration, divided by ultrasound risk categories. Data are expressed as the mean ± SD.

	<10 mm	10–20 mm	>20 mm
Low risk; (341)	18 (5.3%)	164 (48.1%)	159 (46.6%)	<10 versus 10–20 < 0.01
				<10 versus >20 < 0.01
				10–20 versus >20 = ns
Intermediate risk; (489)	41 (8.3%)	295 (60.4%)	153 (31.3%)	<10 versus 10–20 < 0.01
				<10 versus >20 < 0.01
				10–20 versus >20 < 0.01
High risk; (29)	11 (37.0%)	13 (44.5%)	5 (18.5%)	<10 versus 10–20 = NS
				<10 versus >20 = NS
				10–20 versus >20 = NS
	Low versus high risk < 0.01	Low versus high risk = NS	Low versus high risk < 0.05
	Low versus intermediate risk = NS	Low versus intermediate risk = NS	Low versus intermediate risk < 0.01
	Intermediate versus high risk < 0.01	Intermediate versus high risk = NS	Intermediate versus high risk = NS