Table 2.
Crude/adjusted hazard ratios and 95% confidence intervals for undergoing surgery.
| Crude | Adjusteda | |||
|---|---|---|---|---|
| HR | (95% CI) | HR | (95% CI) | |
| CM | ||||
| No | 1.00 | (Reference) | 1.00 | (Reference) |
| Yes | 0.20 | (0.18–0.21)*** | 0.18 | (0.17–0.19)*** |
| Age, years | ||||
| <30 | 1.00 | (Reference) | 1.00 | (Reference) |
| 30–39 | 2.65 | (2.24–3.14)*** | 2.36 | (1.99–2.80)*** |
| 40–49 | 3.00 | (2.54–3.54)*** | 2.54 | (2.15–3.00)*** |
| ≥50 | 1.35 | (1.11–1.64)** | 1.24 | (1.02–1.51)* |
| Occupational status | ||||
| White collar | 1.00 | (Reference) | 1.00 | (Reference) |
| Blue collar | 1.18 | (1.11–1.27)*** | 1.15 | (1.07–1.23)*** |
| Others | 0.99 | (0.89–1.11) | 0.90 | (0.81–1.01) |
| Area | ||||
| Northern Taiwan | 1.00 | (Reference) | 1.00 | (Reference) |
| Central Taiwan | 1.25 | (1.15–1.37)*** | 1.51 | (1.38–1.65)*** |
| Southern Taiwan | 1.20 | (1.12–1.30)*** | 1.26 | (1.17–1.36)*** |
| Eastern Taiwan and offshore islands | 1.09 | (0.93–1.29) | 1.03 | (0.87–1.22) |
| Co-morbidity (versus no) | ||||
| Excessive menstruation | 1.34 | (1.25–1.44)*** | 1.26 | (1.17–1.36)*** |
| Iron-deficiency anemia | 1.61 | (1.48–1.75)*** | 1.56 | (1.43–1.70)*** |
| Dysmenorrhea | 1.23 | (1.14–1.32)*** | 1.35 | (1.25–1.47)*** |
| Infertility | 0.68 | (0.12–1.09) | — | |
aAdjusted for age, occupation, area, excessive menstruation, iron-deficiency anemia, and dysmenorrhea.
**P < 0.01 and ***P < 0.0001.