Table 2.

Estimates and SEs of the cross-time correlation between 2 mammograms within the same individual and of the cross-time cross-twin correlation between time 1 mammogram in one twin and time 2 mammogram in the other twin

Dense areaaPercent dense areaa
Estimate (SE)PEstimate (SE)P
Correlation within same individual0.86 (0.01)<0.0010.82 (0.01)<0.001
Monozygotic cross-correlation0.71 (0.03)<0.0010.65 (0.03)<0.001
Dizygotic cross-correlation0.25 (0.07)<0.0010.20 (0.08)0.01
  • aResiduals after square root transformation and adjustment for age and BMI.