Thyroid imaging reporting and data system with MRI morphological features for thyroid nodules: diagnostic performance and unnecessary biopsy rate

Table 3 Classification results of thyroid nodules by the conventional and four improved ACR-TIRADSs

Methods	Classification	Benign	Malignant	Total	Rate of malignancy (%)	p value
ACR-TIRADS						< 0.001^*
	TI-RADS 2	5	0	5	0.0
	TI-RADS 3	253	8	261	3.0
	TI-RADS 4	172	87	259	33.6
	TI-RADS 5	23	180	203	88.7
Restricted diffusion (A)						< 0.001^*
	TI-RADS 2	253	3	256	1.2
	TI-RADS 3	152	18	170	10.6
	TI-RADS 4	26	33	59	55.9
	TI-RADS 5	22	221	243	90.9
Reversed halo sign (B)						< 0.001^*
	TI-RADS 2	251	6	257	2.3
	TI-RADS 3	164	21	185	11.4
	TI-RADS 4	26	32	58	55.2
	TI-RADS 5	12	216	228	94.7
A + B						< 0.001^*
	TI-RADS 2	258	7	265	2.6
	TI-RADS 3	169	32	201	15.9
	TI-RADS 4	23	51	74	68.9
	TI-RADS 5	3	185	188	98.4
A or B						< 0.001^*
	TI-RADS 2	246	2	248	0.8
	TI-RADS 3	147	7	154	4.5
	TI-RADS 4	29	14	43	32.6
	TI-RADS 5	31	252	283	89.0

Abbreviations: ACR American Radiology, TIRADS Thyroid Imaging Reporting and Data System
^*p < 0.05

ISSN: 1470-7330