Non-contrast computed tomography radiomics model to predict benign and malignant thyroid nodules with lobe segmentation: A dual-center study

Table 1 Multi-cohort comparison of thyroid lobes characteristics, n (%)

Characteristics	Training cohort	Validation cohort	Temporal test cohort	External test cohort	P valuea	P valueb	P valuec
Grouped	n = 264	n = 112	n = 97	n = 81	0.203	0.605	0.053
Benign	80 (30)	26 (23)	26 (27)	15 (19)
Malignant	184 (70)	86 (77)	71 (73)	66 (81)
Gender					0.355	0.415	0.463
Female	211 (80)	84 (75)	73 (75)	61 (75)
Male	53 (20)	28 (25)	24 (25)	20 (25)
Age (years), median (P25-P75)	51.00 (38.75-60.00)	48.50 (35.75-58.00)	50.00 (41.00-57.00)	52.00 (41.00-60.00)	0.100	0.944	0.413
BMI, median (P25-P75)	24.46 (22.04-26.30)	24.73 (22.18-27.05)	24.77 (23.11-26.9)	25.01 (24.29-25.78)	0.288	0.161	0.042
Multiple nodules					0.517	0.519	0.036
No	148 (56)	58 (52)	50 (52)	34 (42)
Yes	116 (44)	54 (48)	47 (48)	47 (58)
Tumor size group					0.095	0.001	0.007
Small (≤ 5 mm)	43 (16)	29 (26)	21 (22)	24 (30)
Medium (5-10 mm)	99 (38)	38 (34)	52 (54)	33 (41)
Large (> 10 mm)	122 (46)	45 (40)	24 (25)	24 (30)
Calcify					0.629	0.344	< 0.001
No	192 (73)	78 (70)	76 (78)	42 (52)
Yes	72 (27)	34 (30)	21 (22)	39 (48)
Cystic					0.741	0.399	< 0.001
No	229 (87)	95 (85)	88 (91)	38 (47)
Yes	35 (13)	17 (15)	9 (9)	43 (53)
FT3 (pmol/L), median (P25-P75)	4.76 (4.39-5.09)	4.76 (4.44-4.99)	4.71 (4.46-5.03)	4.79 (4.32-5.45)	0.891	0.918	0.299
FT4 (pmol/L), median (P25-P75)	16.20 (14.88-17.90)	16.20 (14.57-18.30)	17.40 (15.70-19.00)	16.80 (14.50-19.60)	0.976	0.002	0.204
TSH (mU/L), median (P25-P75)	1.73 (1.37-2.44)	1.62 (1.13-2.59)	2.16 (1.38-2.67)	1.68 (1.04-3.01)	0.098	0.153	0.665
TGAb (IU/mL), median (P25-P75)	16.70 (15.4-21.45)	16.70 (15.3-17.72)	17.00 (15.81-17.90)	17.80 (17.30-18.10)	0.173	0.789	0.001
TPOAb (IU/mL), median (P25-P75)	13.00 (12.35-13.22)	13.00 (11.35-15.10)	15.00 (14.20-15.74)	12.60 (12.10-13.50)	0.707	< 0.001	< 0.001

^aThe significant difference between the training cohort and the validation cohort.

^bThe significant difference between the training cohort and the temporal test cohort.

^cThe significant difference between the training cohort and the external test cohort.

Biased data are expressed as median (interquartile range) for continuous variables and as n (%) for categorical variables. The Mann-Whitney U test was applied to compare continuous variables, and the χ²d test was used for categorical variables. BMI: Body mass index; FT3: Free triiodothyronine; FT4: Free thyroxine; TSH: Thyroid-stimulating hormone; TGAb: Thyroglobulin antibody; TPOAb: Thyroid peroxidase antibody.