Effect of Different Breast Densities and Average Glandular Dose on Contrast to Noise Ratios in Full-Field Digital Mammography: Simulation and Phantom Study
Table 7
Results of multivariate linear regression analysis using CNR as the objective variable and phantom type and phantom thickness as the explanatory variables.
Regression results
Analysis of variance
Variable
Level
Regression coefficient
Lower limit of 95% confidence interval
Upper limit of 95% confidence interval
Wald test p value
Contribution rate
Chi-squared test p value
Constant term
-
24.629
23.228
26.029
1.038.E-17
-
-
Phantom type
B
-1.3
-2.597
-0.003
4.946.E-02
3.63%
9.247.E-03
Phantom type
C
-2.157
-3.454
-0.861
2.684.E-03
-
-
Phantom thickness
-
-0.223
-0.249
-0.196
2.108.E-12
91.43%
2.108.E-12
AIC 71.01658, CNR: contrast to noise ratio, and AIC: Akaike's Information Criterion.