Table 2.

The prognostic factors identified in the univariate and multivariate Cox regression models in the training cohort incorporating covariates identified by the smallest AIC value

Characteristics	Univariate Cox analysis				Multivariate Cox analysis
	Hazard ratio	95%CI		p value	Hazard ratio	95%CI		p value
Age
< =40	R			< 0.001	R			< 0.001
< =60	1.328	1.148	1.537	< 0.001	1.231	1.062	1.427	0.006
> 60	1.870	1.621	2.159	< 0.001	1.724	1.483	2.003	< 0.001
Race
White	R			< 0.001	R			< 0.001
black	1.394	1.268	1.533	< 0.001	1.275	1.154	1.407	< 0.001
Othersa	0.884	0.756	1.033	0.122	0.922	0.788	1.079	0.311
Marital status
Unmarriedb	R			< 0.001	R			< 0.001
Married	0.666	0.616	0.719		0.751	0.694	0.813
Histology
IDC	R			0.189	Not included
ILC	0.916	0.801	1.048	0.202
IDC and ILC	0.882	0.738	1.053	0.164
Grade
I	R			< 0.001	R			< 0.001
II	1.228	1.036	1.454	0.018	1.401	1.180	1.662	< 0.001
III/IV	1.743	1.476	2.058	< 0.001	1.792	1.504	2.135	< 0.001
Subtype
HR+/HER2-	R			< 0.001	R			< 0.001
HR−/HER2+	0.988	0.860	1.135	0.862	0.972	0.835	1.132	0.715
HR+/HER2+	0.801	0.717	0.895	< 0.001	0.832	0.739	0.938	0.003
HR−/HER2-	1.926	2.649	3.232	< 0.001	2.969	2.642	3.337	< 0.001
T stage
T1	R			< 0.001	R			0.001
T2	1.005	0.878	1.151	0.938	1.011	0.882	1.159	0.875
T3	1.162	1.003	1.345	0.045	1.059	0.913	1.229	0.450
T4	1.507	1.321	1.720	< 0.001	1.213	1.059	1.389	0.005
N stage
N0	R			0.244	Not included
N1	0.930	0.811	1.066	0.298
N2	0.827	0.685	0.998	0.047
N3	0.966	0.810	1.151	0.696
Bone metastasis
No	R			< 0.001	R			< 0.001
Yes	0.856	0.787	0.932		1.208	1.099	1.327
Brain metastasis
No	R			< 0.001	R			< 0.001
Yes	2.314	2.040	2.626		1.962	1.724	2.233
Liver metastasis
No	R			< 0.001	R			< 0.001
Yes	1.534	1.416	1.661		1.728	1.586	1.883
Lung metastasis
No	R			< 0.001	R			< 0.001
Yes	1.570	1.453	1.697		1.335	1.228	1.452
Surgery
No	R			< 0.001	R			< 0.001
BCS	0.547	0.476	0.628	< 0.001	0.606	0.526	0.699	< 0.001
Mastectomy	0.724	0.654	0.802	< 0.001	0.762	0.686	0.845	< 0.001
Radiotherapy
No/Unknown	R			0.003	Not included
Yes	0.885	0.818	0.958
chemotherapy
No/Unknown	R			< 0.001	R			< 0.001
Yes	0.674	0.624	0.727		0.564	0.516	0.617

^aOther races included American Indian/Alaska Native, Asian or Pacific Islander

^bUnmarried included divorced, separated, widowed, single (never married) or domestic partner