| |
Cases
|
Controls
|
Pvalue#
|
|---|
| |
n
|
%
|
n
|
%
| |
|---|
|
Overall
|
398
| |
372
| | |
|
Age*
| | | | | |
|
≤ 40
|
79
|
19.8
|
69
|
18.6
|
0.08
|
|
41–45
|
106
|
26.6
|
98
|
26.4
| |
|
46–50
|
144
|
36.2
|
113
|
30.4
| |
|
51–55
|
69
|
17.3
|
91
|
24.5
| |
|
Missing
|
0
|
-
|
1
|
-
| |
|
Mean (SD)
|
44.8
|
(6.2)
|
45.2
|
(6.6)
|
0.37
|
|
BMI
| | | | | |
|
<18.5
|
7
|
2.2
|
4
|
1.1
|
0.05
|
|
18.5 – 25
|
178
|
55.1
|
166
|
46.0
| |
|
25 – 30
|
81
|
25.1
|
116
|
32.1
| |
|
> 30
|
57
|
17.6
|
75
|
20.8
| |
|
Missing
|
75
|
-
|
11
|
-
| |
|
Mean (SD)
|
25.7
|
(5.4)
|
26.3
|
(5.5)
|
0.14
|
|
Education
| | | | | |
|
Up to high school
|
122
|
35.4
|
101
|
27.2
|
0.06
|
|
Technical school
|
27
|
7.8
|
34
|
9.2
| |
|
Some college/University
|
196
|
56.8
|
236
|
63.4
| |
|
Missing
|
53
|
-
|
1
|
-
| |
|
Smoking status
| | | | | |
|
Ever smoked
|
184
|
53.2
|
209
|
56.3
|
0.40
|
|
Never smoked
|
162
|
46.8
|
162
|
43.7
| |
|
Missing
|
52
|
-
|
1
|
-
| |
|
Family History
| | | | | |
|
Yes‡
|
86
|
21.6
|
34
|
9.2
|
<10-5
|
|
No
|
312
|
78.4
|
337
|
90.8
| |
|
Missing
|
0
|
-
|
1
|
-
| |
|
Menopausal status
| | | | | |
|
Pre-menopausal
|
296
|
84.0
|
261
|
82.1
|
0.42
|
|
Post-menopausal
|
56
|
16.0
|
57
|
17.9
| |
|
Missing†
|
46
|
-
|
54
|
-
| |
|
Age at menarche
| | | | | |
|
Age ≤ 12
|
154
|
45.2
|
177
|
48.1
|
0.43
|
|
Age > 12
|
187
|
54.8
|
191
|
51.9
| |
|
Missing
|
57
|
-
|
4
|
-
| |
|
Age period stopped
| | | | | |
|
Pre-menopausal
|
296
|
84.6
|
261
|
82.1
|
0.68
|
|
Age ≤ 49
|
39
|
11.1
|
42
|
13.2
| |
|
Age > 49
|
15
|
4.3
|
15
|
4.7
| |
|
Missing
|
48
|
-
|
54
|
-
| |
|
Parity (# of live births)
| | | | | |
|
Nulliparous
|
68
|
19.6
|
63
|
17.0
|
0.85
|
|
1 child
|
56
|
16.1
|
57
|
15.4
| |
|
2 children
|
145
|
41.8
|
157
|
42.3
| |
|
≥ 3 children
|
78
|
22.4
|
94
|
25.3
| |
|
Missing
|
51
|
-
|
1
|
-
| |
|
Age at 1
st
live birth
| | | | | |
|
Nulliparous
|
68
|
19.7
|
63
|
17.0
|
0.63
|
|
≤ 24 years
|
126
|
36.4
|
136
|
36.7
| |
|
> 24 years
|
152
|
43.9
|
172
|
46.4
| |
|
Missing
|
52
|
-
|
1
|
-
| |
- *Age of first breast cancer diagnosis for cases and age at interview for controls
-
†Uncertain or missing data
-
‡ Women with first-degree relatives with breast cancer
-
# χ2 test for categorical variables or Student's t test (equal variance) for continuous variables
