Table 2. Effects of nodule size on the diagnostic performance of different US parameters and Q-USE in the diagnosis of cytologically indeterminate (Thy 3) thyroid follicular lesions.

Major diameter <1 cm (n = 32)
	Malignantnodules	Benignnodules	Sensitivity	Specificity	NPV	PPV	Accuracy		OR			p value
Echogenicity
Ipoechoic/mixed	11	10	91.7	50.0	90.9	52.4	70.8		11.0			0.016
Others	1	10	(61.5–99.8)	(27.2–72.8)	(58.7–99.8)	(29.8–74.3)	(56.9–84.7)		(1.46-nd)
Microcalcifications
Present	8	8	66.7	60.0	75.0	50.0	63.3		3.0			0.144
Absent	4	12	(34.9–90.1)	(36.1–80.9)	(47.6–92.7)	(24.7–75.3)	(45.6–81.1)		(0.7–12.8)
Irregular margins
Present	12	0	100	100	100	100	100		nd			<0.001
Absent	0	20	(73.5–100)	(83.2–100)	(83.2–100)	(73.5–100)	(100–100)		nd
Strain ratio
<2.05	1	16	91.7	80.0	94.1	73.3	85.8		44.0			<0.001
>2.05	11	4	(61.5–99.8)	(56.3–94.3)	(71.3–99.9)	(44.9–92.2)	(73.7–98.0)		(5.2-nd)
Major diameter >1 cm (n = 108)
Echogenicity
Ipoechoic or mixed	20	33	71.4	58.8	85.5	37.7	65.1		3.6			0.006
Others	8	47	(51.3–86.8)	(47.2–69.6)	(73.3–93.5)	(24.8–52.1)	(55.0–75.2)		(1.4–8.9)
Microcalcifications
Present	12	28	42.9	65.0	76.5	30.0	53.9		1.4			0.459
Absent	16	52	(24.5–62.8)	(53.5–75.3)	(64.6–85.9)	(16.6–46.5)	(43.2–64.6)		(0.6–3.3)
Irregular margins
Present	16	8	57.1	90.0	85.7	66.7	73.6		12.0			<0.001
Absent	12	72	(37.2–75.5)	(81.2–95.6)	(76.4–92.4)	(44.7–84.4)	(63.7–83.5)		(4.3–33.6)
Strain ratio
<2	4	76	85.7	95.0	95.0	85.7	90.4		114.0			<0.001
>2	24	4	(67.9–96.0)	(87.7–98.6)	(87.7–98.6)	(67.3–96.0)	(83.3–97.4)		(27.3–476.0)

NPV, negative predictive value; PPV, positive predictive value; OR, odds ratio. In brackets the 95% confidence interval. nd, non-determinable.