TABLE III.
Characteristics of the Selected Features in Table II and Analysis of Their Changes Over Three “Prior” Screening Cycles
| Selected feature | Prior #1 Mean (SD) | Prior #2 Mean (SD) | Prior #3 Mean (SD) | P-value a | P-value b | P-value c | |||
|---|---|---|---|---|---|---|---|---|---|
|
| |||||||||
| Positive | Negative | Positive | Negative | Positive | Negative | ||||
| CW-SSIM (dense breast region) | 0.410 (0.037) | 0.425 (0.025) | 0.408 (0.041) | 0.423 (0.044) | 0.407 (0.042) | 0.427 (0.036) | <0.01 | <0.01 | <0.01 |
| Maximum short run low GL emphasis (whole breast) | 3.06e−4 (4.17e−4) | 1.86e−4 (1.71e−4) | 2.77e−4 (3.63e−4) | 1.99e−4 (2.50e−4) | 2.87e−4 (3.98e−4) | 3.09e−4 (5.31e−4) | 0.001 | 0.02 | 0.67 |
| CB-SSIM of WLD gradient orientation image (p = 24) | 0.280 (0.073) | 0.263 (0.066) | 0.275 (0.072) | 0.269 (0.080) | 0.274 (0.072) | 0.274 (0.070) | 0.03 | 0.49 | 0.95 |
| PD computed with max. intensity of segmented breast | 1.25e−4 (2.91e−4) | 8.46e−5 (2.86e−4) | 1.17e−4 (2.35e−4) | 8.34e−5 (1.83e−4) | 2.29e−4 (7.72e−4) | 5.62e−5 (1.51e−4) | 0.20 | 0.14 | <0.01 |
| Standard deviation of directional gradient computed along x axis | 222.5 (143.3) | 201.4 (128.1) | 230.6 (139.4) | 194.4 (121.3) | 217.6 (147.3) | 191.7 (132.2) | 0.16 | 0.01 | 0.09 |
| Mean contrast (whole breast region) | 26.4 (24.1) | 22.8 (17.9) | 24.1 (20.2) | 27.9 (23.6) | 29.0 (33.4) | 27.1 (25.7) | 0.12 | 0.12 | 0.55 |
a
P-value from t-test for positive versus negative cases in “prior” #1 images,
b
”prior” #2 images, and
c
”prior” #3 images.