|
Demographic, medical history, and reproductive characteristics of breast cancer cases and controls |
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| Cases (n = 116) No. (%) |
Controls (n = 116) No. (%) |
Odds ratio (95% CI) |
χ2for trend (P) |
|
|
|
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| Age (years) |
||||
| < 50 |
28 (24) |
43 (37) |
0.6 (0.3–1.4) |
|
| 50–54 |
43 (37) |
33 (28) |
1.3 (0.6–2.0) |
|
| 55–59 |
25 (22) |
24 (21) |
1 (ref.) |
|
| 60 ≥ |
20 (17) |
16 (14) |
1.2 (0.5–2.9) |
|
| 1.0 (0.3) |
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| Mean (SD) |
54.6 (6.8) |
52.7 (6.8) |
0.03* |
|
| Marital status |
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| never married |
7 (6) |
4 (4) |
1.0 (ref.) |
|
| married |
86 (74) |
84 (72) |
0.7 (0.2–2.5) |
|
| widowed/divorced |
23 (20) |
28 (24) |
0.6 (0.1–2.3) |
|
| 0.7 (0.4) |
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| Educational status |
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| illiterate |
22 (19) |
29 (25) |
1.0 (ref.) |
|
| primary education |
36 (31) |
31 (27) |
1.5 (0.7–3.3) |
|
| secondary education |
38 (33) |
42 (36) |
1.2 (0.6–2.6) |
|
| higher education |
20 (17) |
14 (12) |
1.9 (0.7–4.8) |
|
| 0.9 (0.4) |
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| Family history of breast cancer |
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| none |
88 (76) |
94 (81) |
1.0 (ref.) |
|
| first or second degree |
28 (24) |
22 (19) |
1.4 (0.2–9.7) |
|
| 0.7 (0.4) |
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| Age at menarche (years) |
||||
| < 13 |
28 (24) |
18 (16) |
1.0 (ref.) |
|
| 13 |
36 (32) |
33 (28) |
0.8 (0.3–1.7) |
|
| 14 |
26 (22) |
37 (32) |
0.5 (0.2–1.1) |
|
| 14 > |
26 (22) |
28 (24) |
0.6 (0.3–1.4) |
|
| 2.2 (0.1) |
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| Parity |
||||
| nulliparous |
11 (9) |
7 (6) |
1.0 (ref.) |
|
| multiparous |
105 (91) |
109 (94) |
0.7 (0.2–1.9) |
|
| 0.7 (0.4) |
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| Age at first live birth (years) |
||||
| 14–19 |
36 (34) |
46 (42) |
1.0 (ref.) |
|
| 20–24 |
44 (42) |
43 (40) |
1.3 (0.7–2.4) |
|
| 25–29 |
17 (16) |
13 (12) |
1.7 (0.7–4.0) |
|
| 30 ≥ |
8 (8) |
7 (6) |
1.7 (0.5–5.2) |
|
| 1.6 (0.2) |
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| Number of live births |
||||
| none |
11 (9) |
7 (6) |
1.0 (ref.) |
|
| 1–2 |
27 (24) |
33 (28) |
0.6 (0.2–1.8) |
|
| 3–4 |
45 (39) |
32 (28) |
0.9 (0.3–2.9) |
|
| > 4 |
33 (28) |
44 (38) |
0.5 (0.2–1.5) |
|
| 0.8 (0.4) |
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| Age at menopause (years) |
||||
| < 45 |
29 (25) |
40 (35) |
1.0 (ref.) |
|
| 45–50 |
59 (51) |
53 (45) |
1.6 (0.8–3.0) |
|
| > 50 |
28 (24) |
23 (20) |
1.7 (0.8–3.7) |
|
| 1.9 (0.2) |
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| Previous use of oral contraceptives |
||||
| none |
73 (63) |
75 (65) |
1.0 (ref.) |
|
| yes |
43 (37) |
41 (35) |
1.1 (0.6–2.0) |
|
| 0.1 (0.8) |
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|
* Derived from t-test. | ||||
Montazeri et al. BMC Cancer 2008 8:278 doi:10.1186/1471-2407-8-278 |
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