Table 5.

Risk of breast cancer according to continuous percent and absolute density for all case-control triplets (n = 813)

Regression coefficientPRegression coefficientP
Percent dense volume* (%)Dense volume* (cm3)
UnadjustedSeparate predictors0.22520.0050.15970.001
Both in the model0.08730.410.09790.10
Adjusted for risk factorsSeparate predictors0.27970.0030.17050.002
Both in the model0.11500.290.10620.09
Percent dense area (%)Dense area (cm2)
UnadjustedSeparate predictors0.12620.0010.11480.001
Both in the model0.09930.050.07590.07
Adjusted for risk factorsSeparate predictors0.2041<0.00010.12270.001
Both in the model0.17420.0020.08580.05
  • NOTE: Unconditional logistic regression analysis.

  • * Cubic root transformed.

  • Age at mammogram (y), age at first birth (y), weight (kg), height (cm), menopausal status (premenopausal, postmenopausal), and parity (parous, nonparous).

  • Square root transformed.