Table 1.
Selected baseline characteristics of the California Teachers Study (CTS) cohort included in the present analysis (n= 90,371)
| Characteristic | n | (%) |
|---|---|---|
| Age at baseline (years) | ||
| <35 | 10,456 | (11.6%) |
| 35–44 | 18,546 | (20.5%) |
| 45–54 | 28,275 | (31.3%) |
| 55–64 | 16,229 | (18.0%) |
| 65–74 | 11,496 | (12.7%) |
| 75–84 | 5,369 | (5.9%) |
| Race/ethnicity | ||
| White | 78,468 | (86.8%) |
| Non-white | 11,266 | (12.5%) |
| Unknown | 637 | (0.7%) |
| Parity (full-term pregnancies) | ||
| None | 23,810 | (26.3%) |
| 1–2 | 43,674 | (48.3%) |
| ≥3 | 21,412 | (23.7%) |
| Unknown | 1,475 | (1.6%) |
| Oral contraceptive use (years) | ||
| None | 26,643 | (29.5%) |
| <5 | 27,608 | (30.5%) |
| ≥5 | 32,463 | (35.9%) |
| Unknown | 3,657 | (4.0%) |
| Lifetime strenuous physical activity (average hours/week) | ||
| <0.5 | 25,254 | (27.9%) |
| 0.5–3.9 | 49,467 | (54.7%) |
| ≥4.0 | 15,293 | (16.9%) |
| Unknown | 357 | (0.4%) |
| Menopausal status | ||
| Pre-menopausal | 42,204 | (46.7%) |
| Peri-menopausal | 2,202 | (2.4%) |
| Post-menopausal | 39,744 | (44.0%) |
| Unknown | 6,221 | (6.9%) |
| Hormone therapy (HT) use (peri-/post-menopausal women only) | ||
| None | 12,968 | (30.9%) |
| Combination estrogen + progestin HT | 14,235 | (33.9%) |
| Estrogen-only HT, ≤5 years | 4,342 | (10.4%) |
| Estrogen-only HT, >5 years | 4,899 | (11.7%) |
| Estrogen-only HT, unknown duration | 332 | (0.8%) |
| Mixed combination and estrogen-only HT | 4,776 | (11.4%) |
| Unknown | 394 | (0.9%) |
| Region of residence within Californiaa | ||
| Greater San Francisco Bay Area | 18,444 | (20.4%) |
| Southern Coastal/Los Angeles Area | 35,388 | (39.2%) |
| Other areas | 36,483 | (40.4%) |
| Unknown | 56 | (0.1%) |
| Type of residence | ||
| Rural | 12,677 | (14.0%) |
| Town | 3,136 | (3.5%) |
| Small city | 16,135 | (17.9%) |
| Metropolitan suburban | 48,278 | (53.4%) |
| Metropolitan urban | 9,038 | (10.0%) |
| Unknown | 1,107 | (1.2%) |
| Statewide percentile of socioeconomic status in census block groupa | ||
| ≤49th | 18,962 | (21.0%) |
| 50–59th | 10,199 | (11.3%) |
| 60–69th | 12,620 | (14.0%) |
| 70–79th | 14,508 | (16.1%) |
| 80–89th | 16,864 | (18.7%) |
| 90–99th | 16,076 | (17.8%) |
| Unknown | 1,142 | (1.3%) |
| Smoking history | ||
| Never | 60,868 | (67.4%) |
| Former | 24,989 | (27.7%) |
| Current | 4,428 | (4.9%) |
| Unknown | 86 | (0.1%) |
| Alcohol drinking in the year prior to baseline | ||
| None | 31,024 | (34.3%) |
| Beer only | 2,222 | (2.5%) |
| Wine only | 19,365 | (21.4%) |
| Liquor only | 2,868 | (3.2%) |
| Beer and liquor only | 1,005 | (1.1%) |
| Wine and beer/liquor | 33,887 | (37.5%) |
a See Methods for definition