Table 4

Logistic and LASSO regression analyses of candidate predictors of endometriosis

Candidate predictorsUnivariable logistic regressionMultivariable logistic regressionLogistic regression with backward stepwise selection‡LASSO regression
BOR (95% CI)BOR (95% CI)BOR (95% CI)B(95% CI)
Intercept−2.60.1 (0.0 to 0.9)−1.50.2 (0.1 to 0.3)−1.5(−4.3 to −0.5)
Age at menarche (years)−0.10.9 (0.8 to 1.0)0.11.1 (0.9 to 1.3)
Severe dysmenorrhea* (cont.)0.82.2 (1.8 to 2.8)0.21.2 (0.9 to 1.8)0.1(0.0 to 0.5)
Absenteeism from school† (cont.)1.13.0 (2.2 to 3.9)0.92.5 (1.6 to 3.7)1.13.0 (2.3 to 4.1)0.8(0.5 to 1.2)
Use of painkillers† (ref. never/rarely)
 Sometimes0.92.3 (1.2 to 4.5)−0.20.8 (0.4 to 2.0)
 Often/always2.39.8 (5.2 to 18.7)0.21.3 (0.5 to 3.5)0.3(0.0 to 1.0)
Use of oral contraceptives†1.64.8 (2.6 to 8.8)0.11.1 (0.5 to 2.6)
Family history of endometriosis2.28.7 (3.2 to 23.5)2.29.4 (2.9 to 30.6)2.39.5 (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.