Table 4.

Traditional multivariable logistic regression

	Odds ratio (95% CI)	p value
Clinical information
Patient age	1.10 (1.09 – 1.12)	< 0.001
Clinically suspicious palpability
No	1 [reference]
Yes	3.90 (2.59 – 5.94)	< 0.001
Breast mass dimensions on B-mode breast ultrasound
Mass size in longest axis	0.89 (0.82 – 0.95)	0.001
Mass size in perpendicular plane	1.12 (1.05 – 1.20)	< 0.001
Mass size in orthogonal plane	1.05 (1.00 – 1.12)	0.098
Tissue composition
Homogeneous background texture; fat	1 [reference]
Heterogeneous background texture	1.21 (0.76 – 1.93)	0.432
Homogeneous background texture; fibroglandular	1.02 (0.61 – 1.69)	0.947
Shape of mass
Oval	1 [reference]
Round	0.86 (0.39 – 1.84)	0.697
Irregular	1.36 (0.82 – 2.27)	0.232
Orientation of mass
Parallel	1 [reference]
Not parallel	2.66 (1.59 – 4.48)	< 0.001
Margin of mass
Circumscribed	1 [reference]
Non-circumscribed	2.67 (1.27 – 5.55)	0.009
Microlobulated margin	2.42 (1.17 – 5.04)	0.017
Indistinct margin	1.42 (0.74 – 2.80)	0.298
Angular margin	2.11 (1.08 – 4.21)	0.031
Spiculated margin	2.69 (0.44 – 5.25)	0.372
Echo pattern
Anechoic	1 [reference]
Complex cystic and solid	-	-
Hypoechoic	-	-
Isoechoic	-	-
Heterogeneous	-	-
Hyperechoic	-	-
Posterior features
None	1 [reference]
Enhancement	1.40 (0.88 – 2.21)	0.152
Combined pattern	1.03 (0.16 – 5.07)	0.969
Shadowing	2.17 (1.23 – 3.83)	0.007
Calcification
No	1 [reference]
Yes	3.08 (1.42 – 6.70)	< 0.001

“-” variable did not converge