Skip to main content

Table 1 Inter-observer agreement on the BI-RADS density classification

From: Inter-observer agreement according to three methods of evaluating mammographic density and parenchymal pattern in a case control study: impact on relative risk of breast cancer

  Reader 2
Reader 1 D1 D2 D3 D4 Total High/low-risk
D1 131
(282)
1
(7)
0
(0)
0
(0)
132
(289)
229; 60%
D2 15
(40)
81
(160)
1
(4)
0
(0)
97
(204)
(493; 64%)
D3 0
(0)
46
(80)
58
(113)
0
(3)
104
(196)
155; 40%
D4 0
(0)
1
(1)
23
(36)
27
(39)
51
(76)
(272; 36%)
Total 146
(322)
129
(248)
82
(153)
27
(42)
384
(765)
P<0.0001
High/low-risk 275; 72%
(570; 75%)
109; 28%
(195; 25%)
  
Agreement Women (%) Breasts (%)   
Absolute agreement: 77.3 77.6   
D1/D2 disagreement: 4.2 6.1   
D2/D3 disagreement: 12.2 11.0   
D3/D4 disagreement: 6.0 5.1   
Two-grade disagreement: 0.3 0.1   
High/low-risk agreement: 87.5 88.9   
  1. Based on 384 women (breasts are shown in brackets; n=765).
  2. Numbers in boldface indicate agreement between the two readers.