Table 2 The within-twin within-trait correlations, the within-twin cross-trait correlation, and the cross-twin cross-trait correlations between the mammogram risk scores (95% confidence intervals in parentheses)

Light areas

Light areas

0.59 (0.54,0.64) *

–

–

Bright areas

Bright areas

0.53 (0.47,0.58) *

–

–

Brightest areas (Cirrocumulus)

Brightest areas (Cirrocumulus)

0.34 (0.27,0.40) *

–

–

Cirrus

Cirrus

0.48 (0.42,0.53) *

–

–

Light areas ^a

Light areas ^a

0.55 (0.50,0.60)

–

–

Bright areas ^a

Bright areas ^a

0.41 (0.35,0.47) *

–

–

Brightest areas (Cirrocumulus) ^a

Brightest areas (Cirrocumulus) ^a

0.22 (0.15,0.29) *

–

–

Light areas

Bright areas

–

0.81 (0.79,0.84)

0.52 (0.47,0.57)

Light areas

Brightest areas (Cirrocumulus)

–

0.49 (0.44,0.55)

0.35 (0.29,0.41)

Light areas

Cirrus

–

0.38 (0.32,0.44)

0.28 (0.21,0.35)

Bright areas

Brightest areas (Cirrocumulus)

–

0.69 (0.65,0.72)

0.40 (0.34,0.46)

Bright areas

Cirrus

–

0.45 (0.39,0.51)

0.33 (0.26,0.39)

Brightest areas (Cirrocumulus)

Cirrus

–

0.43(0.37,0.49)

0.28 (0.22,0.35)

Bright areas^a

Brightest areas (Cirrocumulus)^a

–

0.28 (0.21,0.34)

0.60 (0.57,0.66)

Light areas^a

Brightest areas (Cirrocumulus)^a

–

0.27 (0.21, 0.34)

0.39 (0.33, 0.45)