Table 4 Factors influencing survival time of breast cancer patients by Cox proportional hazard regression model (n = 12,327)

 Did know

1.00

< 0.001

 Didn’t know

0.34

0.05

1.41(1.29–1.54)

< 0.001

 Unclear

1.61

0.11

5.02(4.05–6.22)

< 0.001

Age

0.36

0.02

1.43(1.39–1.48)

< 0.001

Surgery history

−0.44

0.04

0.65(0.59–0.71)

< 0.001

 Primary grade hospital

1.00

< 0.001

 Middle grade hospital

−0.78

0.11

0.46(0.37–0.57)

< 0.001

 High grade hospital

−0.74

0.11

0.48(0.39–0.60)

< 0.001

 1: before 2006

1.00

< 0.001

 2: 2007–2011

−0.22

0.05

0.80(0.73–0.88)

< 0.001

 3: 2012–2016

− 0.43

0.07

0.65(0.59–0.71)

< 0.001

 Stage 0- I

1.00

< 0.001

 Stage II

0.74

0.09

2.09(1.77–2.46)

< 0.001

 Stage Ш

1.61

0.09

4.99(4.17–5.96)

< 0.001

 Stage IV

2.64

0.09

13.95(11.70–16.64)

< 0.001

 Unclassified

1.37

0.08

3.94(3.37–4.60)

< 0.001