TABLE 1—
Baseline Characteristics, by Race/Ethnicity: Study of Women’s Health Across the Nation, 1996–1997
| Whites (n = 1543) | African Americans (n = 930) | Hispanics (n = 284) | Chinese (n = 250) | Japanese (n = 281) | |
| Categorical variable,a no. (%) | |||||
| Premenopausal | 790 (52.3) | 457 (49.5) | 154 (57.9) | 153 (61.9) | 173 (62.2) |
| Education | |||||
| Less than high school | 24 (1.6) | 52 (5.6) | 128 (46.2) | 32 (12.8) | 2 (0.7) |
| High school | 225 (14.6) | 197 (21.3) | 70 (25.3) | 40 (16.0) | 49 (17.4) |
| Some college | 472 (30.7) | 377 (40.8) | 51 (18.4) | 54 (21.6) | 97 (34.5) |
| College | 337 (21.9) | 145 (15.7) | 21 (7.6) | 72 (28.8) | 86 (30.6) |
| More than college | 481 (31.2) | 153 (16.6) | 7 (2.5) | 51 (20.8) | 47 (16.7) |
| Annual household income, $ | |||||
| < 20 000 | 114 (7.5) | 198 (22.1) | 159 (57.4) | 12 (4.9) | 7 (2.6) |
| 20 000–34 999 | 208 (13.6) | 178 (19.9) | 66 (23.8) | 39 (15.9) | 23 (8.7) |
| 35 000–49 999 | 276 (18.0) | 189 (21.1) | 27 (9.8) | 45 (18.4) | 37 (14.0) |
| 50 000–74 999 | 403 (26.4) | 182 (20.3) | 14 (5.0) | 61 (24.9) | 74 (27.9) |
| ≥ 75 000 | 528 (34.5) | 149 (16.6) | 11 (4.0) | 88 (35.9) | 124 (46.8) |
| Difficulty paying for basics | |||||
| Very difficult | 90 (5.8) | 120 (12.9) | 73 (26.4) | 13 (5.2) | 10 (3.6) |
| Somewhat difficult | 407 (26.4) | 312 (33.6) | 156 (56.3) | 57 (22.8) | 74 (26.4) |
| Not very difficult | 1046 (67.8) | 498 (53.5) | 48 (17.3) | 180 (72.0) | 196 (70.0) |
| Employed | 1311 (84.7) | 739 (79.3) | 162 (57.5) | 223 (89.2) | 208 (74.0) |
| Marital status | |||||
| Single | 183 (12.0) | 200 (21.6) | 15 (5.5) | 22 (8.9) | 20 (7.1) |
| Married/partnered | 1085 (71.3) | 439 (47.3) | 198 (73.1) | 199 (80.2) | 227 (81.1) |
| Separated | 46 (3.0) | 67 (7.2) | 30 (11.1) | 3 (1.2) | 11 (3.9) |
| Widowed | 16 (1.1) | 39 (4.2) | 5 (1.8) | 4 (1.6) | 2 (0.7) |
| Divorced | 191 (12.6) | 183 (19.7) | 23 (8.5) | 20 (8.1) | 20 (7.1) |
| Parous | 1169 (75.8) | 851 (91.1) | 258 (93.5) | 216 (86.4) | 234 (83.3) |
| Current smoker | 257 (16.6) | 225 (24.6) | 47 (16.7) | 4 (1.6) | 36 (12.9) |
| Environmental tobacco smoke exposure, no. of person-hours/wk | |||||
| None | 606 (39.3) | 321 (34.7) | 179 (62.8) | 195 (78.0) | 172 (61.9) |
| 1–4 | 488 (31.6) | 238 (25.8) | 32 (11.2) | 39 (15.6) | 62 (22.3) |
| ≥5 | 448 (29.1) | 365 (39.5) | 74 (26.0) | 16 (6.4) | 44 (15.8) |
| Language used in reading/speaking | |||||
| Other than English | 0 (0.0) | 1 (0.1) | 201 (70.8) | 44 (17.8) | 86 (30.6) |
| Bilingual | 11 (0.7) | 1 (0.1) | 73 (25.7) | 110 (44.5) | 46 (16.4) |
| English only | 1526 (99.3) | 922 (99.8) | 10 (3.5) | 93 (37.7) | 149 (53.0) |
| Baseline anxiety (summed score ≥ 4) | 354 (22.9) | 223 (24.1) | 102 (35.7) | 34 (13.6) | 37 (13.2) |
| Depressive symptoms (score ≥ 16) | 351 (22.7) | 254 (27.2) | 123 (43.3) | 35 (14.0) | 41 (14.6) |
| No. of previous premenstrual symptomsb | |||||
| None | 71 (4.6) | 39 (4.2) | 9 (3.2) | 36 (14.8) | 33 (11.9) |
| 1 | 129 (8.3) | 87 (9.3) | 22 (7.7) | 59 (24.2) | 46 (16.5) |
| 2 | 266 (17.2) | 175 (18.8) | 56 (19.7) | 63 (25.8) | 84 (30.2) |
| 3 | 477 (30.8) | 295 (31.6) | 84 (29.6) | 46 (18.8) | 67 (24.1) |
| 4 | 605 (39.1) | 337 (36.1) | 113 (39.8) | 40 (16.4) | 48 (17.3) |
| Continuous variable,c mean (median) | |||||
| Age, y | 46.3 (46.1) | 46.2 (46.1) | 46.3 (46.1) | 46.5 (46.6) | 46.7 (46.7) |
| Body mass index, kg/m2 | 27.8 (26.1) | 31.5 (30.2) | 29.2 (28.3) | 23.3 (22.4) | 22.9 (22.1) |
| Physical activity score (range: 3–14) | 8.0 (8.1) | 7.3 (7.3) | 6.8 (6.6) | 7.3 (7.3) | 7.9 (7.8) |
| Alcohol consumption per day, kcal | 57.4 (13.3) | 33.6 (0.0) | 24.1 (0.0) | 9.5 (0.0) | 36.2 (0.0) |
| Daily genistein intake, μg | 833.6 (3.6) | 270.9 (1.7) | 310.3 (0.0) | 6398 (3661) | 11 165 (7091) |
| Daily caffeine consumption, mg | 278.9 (220.1) | 204.7 (142.0) | 207.3 (161.8) | 164.2 (117.3) | 258.4 (217.3) |
| Symptom sensitivity score at first follow-up visit (range: 0–20) | 10.0 (10.0) | 10.8 (11.0) | 10.3 (11.0) | 9.8 (10.0) | 9.6 (10.0) |
| Social support score (range: 0–16) | 12.6 (13.0) | 12.1 (13.0) | 11.0 (12.0) | 11.8 (12.0) | 13.2 (14.0) |
| Perceived stress score (range: 4–20) | 8.4 (8.0) | 8.5 (8.0) | 10.0 (11.0) | 8.2 (8.0) | 8.8 (9.0) |
aAll Ps < .0001.
bAbdominal cramps, breast tenderness, bloating, and mood changes.
cAll Ps < .0001 except for age (P = .1).