Table 3.

Regression estimates and SEs of association between mammographic measures at time 2 and mammographic measures at time 1 adjusting for co-twin and/or zygosity; N = 654

Dense areaaPercent dense areaa
Estimate (SE)PEstimate (SE)P
Model I
 Self0.86 (0.021)<0.0010.77 (0.022)<0.001
 Co-twin
Model IIa
 Self
 Co-twin0.78 (0.024)<0.0010.66 (0.027)<0.001
Model IIb
 Self
 Co-twin
  MZ0.84 (0.031)<0.0010.73 (0.035)<0.001
  DZ0.63 (0.042)<0.0010.42 (0.046)<0.001
Model IIIa
 Self0.83 (0.020)<0.0010.75 (0.023)<0.001
 Co-twin0.063 (0.022)0.0040.066 (0.023)0.004
Model IIIb
 Self0.82 (0.020)<0.0010.74 (0.025)<0.001
 Co-twin
  MZ0.090 (0.031)0.0040.100 (0.032)0.002
  DZ0.035 (0.031)0.30.029 (0.033)0.4
  • aResiduals after square root transformation and adjustment for age and BMI.