Demographic and clinical characteristics of the study population (N=5116)
| Variable | No history n (weighted %) | With history n (weighted %) | χ2 | P value |
| Age | ||||
| ≤44 | 1050 (50.4) | 1396 (46.0) | 322.363 | <0.001 |
| 45–64 | 364 (17.5) | 1153 (38.0) | ||
| ≥65 | 668 (32.1) | 485 (16.0) | ||
| Race | ||||
| Mexican American | 412 (19.8) | 465 (15.3) | 87.855 | <0.001 |
| Other Hispanic | 280 (13.4) | 334 (11.0) | ||
| Non-Hispanic white | 792 (38.0) | 1487 (49.0) | ||
| Non-Hispanic black | 417 (20.0) | 610 (20.1) | ||
| Other race | 181 (8.7) | 138 (4.5) | ||
| Education | ||||
| Less than high school diploma | 540 (37.5) | 664 (22.9) | 135.868 | <0.001 |
| High school diploma | 347 (24.1) | 622 (21.4) | ||
| Some college | 337 (23.4) | 955 (32.9) | ||
| College or more | 215 (14.9) | 661 (22.8) | ||
| Body mass index status | ||||
| Underweight | 90 (4.4) | 64 (2.1) | 67.598 | <0.001 |
| Normal | 735 (35.9) | 864 (28.8) | ||
| Overweight | 581 (28.4) | 865 (28.8) | ||
| Obese | 640 (31.3) | 1212 (40.3) | ||
| Smoking status | ||||
| Never | 989 (68.5) | 1707 (58.8) | 44.868 | <0.001 |
| Former | 265 (18.4) | 611 (21.1) | ||
| Current | 189 (13.1) | 584 (20.1) | ||
| Alcohol use | ||||
| Never or not in the last 12 months | 809 (61.9) | 970 (36.7) | 239.567 | <0.001 |
| 1 drink/day | 230 (17.6) | 617 (23.3) | ||
| 2–3 drinks/day | 186 (14.2) | 793 (30.0) | ||
| 4+ drinks/day | 81 (6.2) | 266 (10.1) | ||
| First menstrual age | ||||
| <10 | 55 (2.6) | 115 (3.8) | 14.323 | 0.002 |
| 10–12 | 1017 (49.0) | 1347 (44.4) | ||
| 13–15 | 873 (42.0) | 1386 (45.7) | ||
| >16 | 132 (6.4) | 183 (6.0) | ||
| Ever been pregnant | ||||
| No | 233 (16.2) | 357 (12.4) | 12.215 | <0.001 |
| Yes | 1203 (83.8) | 2533 (87.6) | ||
| Currently pregnant | ||||
| No | 25 (9.3) | 44 (4.8) | 7.709 | 0.005 |
| Yes | 243 (90.7) | 871 (95.2) | ||
| Menopause status | ||||
| No | 1133 (54.5) | 1650 (54.4) | 0.004 | 0.951 |
| Yes | 947 (45.5) | 1384 (45.6) | ||
| History of hormone replacement use (not for birth control) | ||||
| No | 1111 (77.3) | 2259 (78.1) | 0.355 | 0.551 |
| Yes | 326 (22.7) | 633 (21.9) | ||
| History of thyroid disease | ||||
| No | 1119 (77.5) | 2269 (78.4) | 0.388 | 0.534 |
| Yes | 324 (22.5) | 626 (21.6) | ||
| Current knowledge of thyroid disease | ||||
| No | 66 (20.6) | 109 (17.8) | 1.091 | 0.296 |
| Yes | 254 (79.4) | 503 (82.2) | ||
| Thyroid status | ||||
| Hyperthyroid | 37 (1.8) | 55 (1.8) | 11.507 | 0.003 |
| Hypothyroid | 294 (14.1) | 536 (17.7) | ||
| Euthyroid | 1751 (84.1) | 2443 (80.5) | ||