Descriptive statistics of subjects stratified by case or control status (total observations with percentage in parentheses)
Variable | Cases (n = 428) | Controls (n = 426) | Total (n = 854) | Pa |
---|---|---|---|---|
Age at entry (yrs) | ||||
<50 | 58 (13.5) | 86 (20.2) | 144 (16.9) | |
50–54 | 61 (14.3) | 76 (20.2) | 137 (16.0) | |
55–59 | 65 (15.2) | 65 (15.3) | 130 (15.2) | |
60–64 | 79 (18.5) | 59 (13.9) | 138 (16.2) | |
65–69 | 90 (21.0) | 83 (19.5) | 173 (20.3) | |
70–74 | 69 (16.1) | 51 (12.0) | 120 (14.1) | |
≥75 | 6 (1.4) | 6 (1.4) | 12 (1.4) | 0.05 |
Ethnicity | ||||
African American | 117 (27.3) | 117 (27.5) | 234 (27.4) | |
Japanese | 100 (23.4) | 100 (23.5) | 200 (23.4) | |
Latina | 101 (23.6) | 99 (23.2) | 200 (23.4) | |
White | 110 (25.7) | 110 (25.8) | 220 (25.8) | 0.9995 |
Family history of breast cancer | ||||
Reported | 77 (18.0) | 42 (9.9) | 119 (13.9) | 0.0090 |
Any <50 yrs | 33 (7.7) | 17 (4.0) | 50 (5.9) | 0.0015 |
Family history of ovarian cancer | 19 (4.4) | 21 (4.9) | 40 (4.7) | 0.8594 |
Age at first menstrual period (yrs) | ||||
<13 | 229 (54.1) | 211 (49.9) | 440 (52.0) | |
13 | 194 (45.9) | 212 (50.1) | 406 (48.0) | 0.2420 |
No. of children | ||||
None | 29 (7.8) | 25 (6.7) | 54 (7.5) | |
1–2 | 79 (21.2) | 104 (27.9) | 183 (25.3) | |
2–3 | 129 (34.6) | 141 (37.8) | 270 (37.3) | |
4 or more | 114 (30.6) | 103 (27.6) | 217 (30.0) | 0.2475 |
Age of first full-term pregnancy (yrs)b | ||||
<20 | 108 (29.3) | 129 (34.6) | 237 (32.1) | |
21–25 | 129 (34.9) | 141 (37.8) | 270 (36.5) | |
26–30 | 87 (23.6) | 78 (20.9) | 162 (21.9) | |
31 | 45 (12.2) | 25 (6.7) | 70 (9.5) | 0.0356 |
a P was calculated by the χ2 test for heterogeneity (categorical variables) comparing cases with controls.
b Among parous women.