Table 4.
Logistic and LASSO regression analyses of candidate predictors of endometriosis
| Candidate predictors | Univariable logistic regression | Multivariable logistic regression | Logistic regression with backward stepwise selection‡ | LASSO regression | ||||
| B | OR (95% CI) | B | OR (95% CI) | B | OR (95% CI) | B | (95% CI) | |
| Intercept | −2.6 | 0.1 (0.0 to 0.9) | −1.5 | 0.2 (0.1 to 0.3) | −1.5 | (−4.3 to −0.5) | ||
| Age at menarche (years) | −0.1 | 0.9 (0.8 to 1.0) | 0.1 | 1.1 (0.9 to 1.3) | ||||
| Severe dysmenorrhea* (cont.) | 0.8 | 2.2 (1.8 to 2.8) | 0.2 | 1.2 (0.9 to 1.8) | 0.1 | (0.0 to 0.5) | ||
| Absenteeism from school† (cont.) | 1.1 | 3.0 (2.2 to 3.9) | 0.9 | 2.5 (1.6 to 3.7) | 1.1 | 3.0 (2.3 to 4.1) | 0.8 | (0.5 to 1.2) |
| Use of painkillers† (ref. never/rarely) | ||||||||
| Sometimes | 0.9 | 2.3 (1.2 to 4.5) | −0.2 | 0.8 (0.4 to 2.0) | ||||
| Often/always | 2.3 | 9.8 (5.2 to 18.7) | 0.2 | 1.3 (0.5 to 3.5) | 0.3 | (0.0 to 1.0) | ||
| Use of oral contraceptives† | 1.6 | 4.8 (2.6 to 8.8) | 0.1 | 1.1 (0.5 to 2.6) | ||||
| Family history of endometriosis | 2.2 | 8.7 (3.2 to 23.5) | 2.2 | 9.4 (2.9 to 30.6) | 2.3 | 9.5 (3.1 to 29.2) | 1.7 | (1.0 to 3.0) |
Only participants with complete data for the candidate predictors (154 cases and 145 controls) were included in the analyses.
*Experienced in adolescence.
†Due to dysmenorrhea in adolescence.
‡Backward stepwise variable selection was performed using Wald test statistics with p≤0.157 as the criterion for inclusion.
cont., continuous; LASSO, least absolute shrinkage and selection operator; ref., reference.