highly significantp < 0.05
The test revealed highly significant improvements ( p < 0.05) for PneuNet over VGG-16 ( χ 2 = 18.7, p < 0.001), EfficientNet-B4 ( χ 2 = 12.3, p = 0.002), and DenseNet-121 ( χ 2 = 4.1, p = 0.043), confirming that PneuNet’s superior accuracy and balanced sensitivity–specificity are not due to chance.