Table 4.

Partial correlation coefficients of components of the lifetime Gail breast cancer risk score with mammographic density

SD
DOV
TOV
DOA
TOA
PD
Average
Proportion of variance explained (%)
rPrPrPrPrPrPr
(a) Hereditary factors
    No. first-degree relatives affected by breast cancer0.2333*0.0250.2255*0.0310.2364*0.0230.2305*0.0270.2368*0.0230.2328*0.0260.232812
(b) Hormonal exposure
    Early menarche (<age 12 years)0.03810.7180.04030.7030.03090.7700.04550.6660.03540.7380.04790.6500.03972
    Nulliparity−0.14140.179−0.14740.161−0.13760.191−0.14060.181−0.12970.218−0.14050.182−0.13957
    Late age at first birth (>age 30 years)−0.10180.334−0.11560.273−0.10690.310−0.10550.317−0.09790.353−0.10750.308−0.10595
(c) Breast tissue changes
    No. prior breast biopsies0.15610.1370.17260.1000.15340.1440.17920.0870.16390.1180.15940.1290.16418
    History of AH or LCIS0.6417*0.0000.6383*0.0000.6427*0.0000.6399*0.0000.6416*0.0000.6454*0.0000.641633
Remaining correlation between density variable and Gail risk0.11930.2570.15050.1520.15420.1420.10970.2980.10920.3000.13460.2010.12967
(d) Current age0.5148*0.0000.5092*0.0000.4792*0.0000.5228*0.0000.4942*0.0000.5056*0.0000.504326
  • Abbreviations: r, partial correlation coefficient; P, probability of type I error; SD, subjective density; AH, atypical hyperplasia.

  • * P < 0.05.