Operating-Point Collapse Under Normal-Class Source Confounding in Cross-Dataset Breast Ultrasound Classification

Background

Public breast ultrasound datasets are assembled around lesions. Of eight sources examined here, five contain no normal images, and under leave-one-dataset-out evaluation, the normal class is therefore almost perfectly confounded with the acquisition source: with one site held out, 356 of the 358 normal training images come from a single other source, supplied by 28 of that source’s 38 patients.