Table 2 Association between mammographic measures and breast cancer risk

 VDG1

58/46,089

ref

NA

ref

 VDG2

215/99,086

1.78 (1.33 ; 2.38)

NA

1.89 (1.38 ; 2.58)

 VDG3

189/73,207

2.38 (1.76 ; 3.20)

NA

2.53 (1.83 ; 3.49)

 VDG4

61/20,314

3.14 (2.17 ; 4.55)

NA

3.54 (2.39 ; 5.24)

P trend

<0.001

<0.001

 Q1 (<4.8%)

79/58,411

ref

NA

ref

 Q2 (4.8–6.4%)

127/61,153

1.57 (1.19 ; 2.08)

NA

1.61 (1.19 ; 2.18)

 Q3 (6.4–9.8%)

161/60,499

2.17 (1.65 ; 2.84)

NA

2.33 (1.74 ; 3.11)

 Q4 (>9.8%)

156/58,633

2.42 (1.83 ; 3.20)

NA

2.52 (1.87 ; 3.40)

P trend

<0.001

<0.001

Percent dense volume (per SD increase)^#

523/238,696

1.36 (1.25 ; 1.48)

NA

1.38 (1.26 ; 1.51)

 C1 (<39.8 cm³)

69/45,851

ref

ref

ref

 C2 (39.9– 65.2 cm³)

197/96,827

1.37 (1.04 ; 1.80)

1.53 (1.15 ; 2.05)

1.69 (1.24 ; 2.30)

 C3 (65.3– 110.1 cm³)

176/74,190

1.66 (1.26 ; 2.20)

2.06 (1.52 ; 2.80)

2.27 (1.63 ; 3.14)

 C4 (>110.1 cm³)

81/21,828

2.79 (2.02 ; 3.86)

3.55 (2.49 ; 5.05)

3.66 (2.50 ; 5.36)

P trend

<0.001

<0.001

<0.001

 Q1 (<42.9 cm³)

91/57,909

ref

ref

ref

 Q2 (42.9–7.8 cm³)

113/59,364

1.22 (0.93 ; 1.61)

1.35 (1.01 ; 1.80)

1.47 (1.08 ; 1.99)

 Q3 (57.9–78.9 cm³)

136/60,359

1.48 (1.13 ; 1.93)

1.77 (1.33 ; 2.35)

1.92 (1.42 ; 2.60)

 Q4 (>78.9 cm³)

183/61,065

2.08 (1.61 ; 2.68)

2.60 (1.96 ; 3.45)

2.71 (2.01 ; 3.67)

P trend

<0.001

<0.001

<0.001

Dense volume (per SD increase)^#

523/238,696

1.34 (1.23 ; 1.46)

1.45 (1.32 ; 1.60)

1.45 (1.32 ; 1.60)