Table 2.
Association Between Household Intactness and Timing of Breast Development Onset: KPNC Puberty Study (2009–2020)
| Unadjusted | Adjusteda | Adjusteda,b | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Household Intactness | N | TR | 95%CI | HR | 95%CI | TR | 95%CI | HR | 95%CI | TR | 95%CI | HR | 95%CI |
|
Non-intact household before age 2 years |
1,915 | 0.96 | 0.96,0.97 | 1.42 | 1.31,1.54 | 0.97 | 0.97,0.98 | 1.29 | 1.19,1.40 | 0.98 | 0.97,0.99 | 1.25 | 1.14,1.36 |
|
Non-intact household during age 2–6 years |
2,070 | 0.98 | 0.98,0.99 | 1.17 | 1.08,1.26 | 0.99 | 0.98,1.00 | 1.13 | 1.04,1.22 | 0.99 | 0.98,1.00 | 1.08 | 1.00,1.17 |
| Intact household | 20,765 | Ref | Ref | Ref | Ref | Ref | Ref | ||||||
CI confidence interval; HR hazard ratio; KPNC Kaiser Permanente Northern California; TR time ratio
aAdjusted for race/ethnicity and median household income
bAdjusted for prepubertal BMI