TABLE 4.

Baseline Predictors of Early Menarche (< 11.0 Years)* in the Longitudinal Sample

Hazard RRs
1-Unit Difference75th Percentile Versus 25th Percentile
Individual predictors
 Race (black vs white)1.56 (1.2, 3.0)
 Height z score1.60 (1.4, 1.8)1.83 (1.5, 2.2)
 Weight z score1.63 (1.4, 1.8)1.95 (1.6, 2.3)
 BMI z score1.52 (1.3, 1.7)1.79 (1.5, 2.1)
 Log triceps skinfold2.31 (1.6, 3.4)1.48 (1.2, 1.8)
 Log subscapular skinfold§1.73 (1.2, 2.4)1.38 (1.1, 1.7)
Joint predictors
 Model 1
  Race (black vs white)1.43 (1.1, 1.8)
  Height z score1.37 (1.2, 1.6)1.51 (1.2, 1.8)
  BMI z score1.37 (1.2, 1.6)1.54 (1.3, 1.8)
 Model 2
  Race (black vs white)1.42 (1.1, 1.8)
  Height z score1.11 (0.9, 1.4)1.15 (0.9, 1.5)
  Weight z score1.50 (1.3, 1.8)1.75 (1.4, 2.2)
 Model 3
  Race (black vs white)1.57 (1.2, 2.1)
  Height z score1.43 (1.2, 2.1)1.59 (1.3, 1.9)
  Log triceps skinfold2.02 (1.4, 3.0)1.39 (1.2, 1.7)
  • * 240 (of the 2058) girls experienced menarche before age 11.0 y.

  • RRs compare the rate of early menarche for girl at the 75th vs 25th percentile of each specified characteristic.

  • All models control for baseline age and year of follow-up; levels of height, weight, and skinfold thicknesses were measured among 5.0- to 9.9-year-olds.

  • § 1007 girls had a subscapular skinfold thickness measurement at baseline

  • P < .01.

  • P < .001.