Table 2.
The comparisons of performance indices and p values (chi-square test or z test) among the morphology features, the texture features, and the combined feature set
| Morphology | Texture | Combined | Morphology vs. texture (p value) | Combined vs. morphology (p value) | Combined vs. texture (p value) | |
|---|---|---|---|---|---|---|
| Accuracy | 84 % (58/69) | 77 % (53/69) | 88 % (61/69) | 0.2833 | 0.4586 | 0.0724 |
| Sensitivity | 86 % (18/21) | 62 % (13/21) | 86 % (18/21) | 0.0793 | 1.0000 | 0.0793 |
| Specificity | 83 % (40/48) | 83 % (40/48) | 90 % (43/48) | 1.0000 | 0.3709 | 0.3709 |
| PPV | 69 % (18/26) | 62 % (13/21) | 78 % (18/23) | 0.5982 | 0.4749 | 0.2349 |
| NPV | 93 % (40/43) | 83 % (40/48) | 93 % (43/46) | 0.1569 | 0.9318 | 0.1261 |
| Az | 0.90 | 0.75 | 0.95 | 0.0703 | 0.2898 | 0.0163* |
Combined feature set includes the morphology features and the texture features
*p < 0.05 (indicates a statistically significant difference)