Table 1 Patient characteristics for model development (Eastern Cancer Registration and Information Centre-ECRIC) and validation (West Midlands Cancer Intelligence Unit-WMCIU) cohorts

Total Number of Subjects

5,694

5,468

Total time at risk (years)

31,904

25,917

Median follow-up (years)*

5.65

(0.04 to 8.00)^†

4.85

(0.07 to 8.00)^†

Number of breast cancer deaths

737

668

Number of other deaths

338

287

Annual breast cancer mortality rate

0.023

(0.021 to 0.025)^‡

0.026

(0.024 to 0.028)^‡

Five-year breast cancer survival rate

0.89

(0.88 to 0.90)^‡

0.88

(0.87 to 0.89)^‡

Median age at diagnosis, years

58

(23 to 95)^†

58

(22 to 93)^†

Number

Number

Age, years

   <35

111

2

108

2

   35 to 49

1,172

21

1,195

22

   50 to 64

2,630

46

2,393

44

   65 to 74

1,124

20

1,101

20

   75+

657

12

671

12

Nodal status

   0

3,532

62

3,184

58

   1

741

13

746

14

   2 to 4

806

14

792

14

   5 to 9

380

7

451

8

   10+

235

4

295

5

Tumour size, mm

   <10

625

11

485

9

   10 to 19

2,310

41

2,136

39

   20 to 29

1,627

29

1,566

29

   30 to 49

845

15

923

17

   50+

287

5

358

7

Grade

   I

1,005

18

1,017

19

   II

2,927

51

2,442

45

   III

1,762

31

2,009

37

Oestrogen Receptor (ER) Status

   ER negative

991

17

1,116

20

   ER positive

4,703

83

4,352

80

Adjuvant therapy

   Chemotherapy

1,905

33

2,121

39

   Endocrine therapy

4,268

75

2,406

44

   Combined chemoendocrine

1,122

20

579

11

Screen detected

   Yes

1,621

28

1,256

23

   No

4,073

72

4,212

77