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Table 5 Ratios of expected (E) to observed (O) numbers of invasive breast cancers diagnosed within 10 years from screening

From: Validation of the Gail model for predicting individual breast cancer risk in a prospective nationwide study of 28,104 Singapore women

Risk factors Based on Gail model
(Caucasian)
Based on Matsuno AABCS model
(Chinese-American and other Asian-American)
  O E E/O 95% CI
for E/O
O E E/O 95% CI
for E/O
Total 409 758.18 1.85 (1.68, 2.04) 409 404.70 0.99 (0.90, 1.09)
Age at menarche, years         
   ≥14 226 477.32 2.11 (1.85, 2.41) 226 253.58 1.12 (0.98, 1.28)
   12-13 161 252.42 1.57 (1.34, 1.83) 161 136.16 0.85 (0.72, 0.99)
   < 12 22 28.44 1.29 (0.85, 1.96) 22 14.96 0.68 (0.45, 1.03)
  χ2 = 166.89, P < 0.001 χ2 = 10.84, P = 0.004
Any breast biopsy
Age at screening: ≥50 years
        
   No 370 706.46 1.91 (1.72, 2.11) 370 366.38 0.99 (0.89, 1.10)
   Yes 39 51.72 1.33 (0.97, 1.82) 39 38.32 0.98 (0.72, 1.34)
  χ2 = 163.37, P < 0.001 χ2 = 0.05, P = 0.827
Number of affected first-degree relatives
Age at first live birth: < 20 years
        
   0 48 93.42 1.95 (1.47, 2.58) 48 41.62 0.87 (0.65, 1.15)
   1 2 4.59 2.30 (0.57, 9.18) 2 1.76 0.88 (0.22, 3.52)
   > 1 0 0.13 - - 0 0.02 - -
Number of affected first-degree relatives
Age at first live birth: 20-24 years
        
   0 113 246.74 2.18 (1.82, 2.63) 113 123.47 1.09 (0.91, 1.31)
   1 9 10.97 1.22 (0.63, 2.34) 9 5.84 0.65 (0.34, 1.25)
   > 1 2 0.62 0.31 (0.08, 1.24) 2 0.15 0.08 (0.02, 0.30)
Number of affected first-degree relatives
Age at first live birth: 25-29 years or nulliparous
        
   0 156 269.37 1.73 (1.48, 2.02) 156 150.21 0.96 (0.82, 1.13)
   1 13 15.78 1.21 (0.70, 2.09) 13 11.19 0.86 (0.50, 1.48)
   > 1 0 0.36 - - 0 0.14 - -
Number of affected first-degree relatives
Age at first live birth: > 30 years
        
   0 62 110.49 1.78 (1.39, 2.29) 62 65.18 1.05 (0.82, 1.35)
   1 3 5.61 1.87 (0.60, 5.80) 3 5.04 1.68 (0.54, 5.21)
   > 1 1 0.09 0.09 (0.01, 0.64) 1 0.08 0.08 (0.01, 0.57)
  χ2 = 179.85, P < 0.001 χ2 = 38.66, P < 0.001
  1. AABCS, Asian American Breast Cancer Study model; CI, confidence interval; E, expected number of breast cancer cases; E/O, ratio of expected to observed number of breast cancer cases; O, observed number of breast cancer cases.
  2. Ratios of expected (E) numbers of invasive breast cancers using 10-year predicted risk based on Gail model and Matsuno model to observed (O) numbers of invasive breast cancers diagnosed within 10 years from screening among Singapore Breast Cancer Screening Project cohort by risk factors in Gail model