Table 4 Comparison of risk factors calculated using the univariate logistic analysis, multivariable logistic analysis and Bootstrap for variables.

Age (years)

   36-60 (a)

2.646 (c v.s. a)

(1.232, 5.650)

0.002

3.937 (c v.s. a)

(1.403, 11.111)

0.003

0.892

(0.945, 12.195)

0.013

   61-85 (b)

1.342 (c.v.s. b)

(0.579, 3.115)

1.548 (c v.s. b)

(0.492, 4.878)

0.924

(0.370, 5.348)

   20-35 (c)

Ultrasound

M

3.584

(2.088, 6.173)

<0.0001

1.977

(1.545, 4.367)

<0.0001

0.471

(1.023, 4.993)

0.111

N, B, I, S

Mammography

BR5

3.717

(1.898, 7.299)

0.0001

3.058

(1.049, 8.929)

0.048

1.315

(1.121, 1.530)

0.028

BR1-4

Diagnostic method

Others

2.331

(1.422, 3.846)

0.001

2.519

(1.172, 5.410)

0.028

0.427

(1.119, 6.303)

0.016

Core biopsy

Tumor grade

III

2.172

(1.486, 3.176)

<0.0001

1.671

(1.215, 2.829)

0.01

0.322

(0.966, 3.347)

0.075

II

I

Lymph node

N3

4.053

(2.850, 5.755)

<0.0001

3.037

(1.808, 5.104)

<0.0001

0.335

(1.624, 6.221)

0.001

N1 or N2

N0

ER/PR

(-, -), (-, +), (+, -)

1.99

(1.194, 3.331)

0.009

2.778

(1.231, 6.260)

0.045

0.451

(1.306, 7.996)

0.011

(+, +)

Chemotherapy

Yes (a)

2.558 (c v.s. a)

(1.263, 5.155)

<0.0001

4.348

(1.631, 11.494)

0.002

0.852

(1.339, 13.514)

0.003

No (b)

16.393 (c v.s. b)

(5.051, 52.632)

12.658

(2.558, 62.5)

3.761

(18.868, 2.87*10⁹)

Abandonment or Refusal (c)