Many real-world image recognition problems, such as diagnostic medical imaging exams, are “long-tailed” – there are a few common findings followed by many more relatively rare conditions. In chest radiography, diagnosis is both a long-tailed and multi-label problem, as patients often present with multiple findings simultaneously. While researchers have begun to study the problem of long-tailed learning in medical image recognition, few have studied the interaction of label imbalance and label co-occurrence posed by long-tailed, multi-label disease classification. To engage with the research community on this emerging topic, we conducted an open challenge, CXR-LT, on long-tailed, multi-label thorax disease classification from chest X-rays (CXRs). We publicly release a large-scale benchmark dataset of over 350,000 CXRs, each labeled with at least one of 26 clinical findings following a long-tailed distribution. We synthesize common themes of top-performing solutions, providing practical recommendations for long-tailed, multi-label medical image classification. Finally, we use these insights to propose a path forward involving vision-language foundation models for few- and zero-shot disease classification.
This work was supported by the National Library of Medicine [grant number R01LM014306], the National Science Foundation [grant numbers 2145640, IIS-2212176], the Amazon Research Award, and the Artificial Intelligence Journal. It was also supported by the NIH Intramural Research Program, National Library of Medicine and Clinical Center. The authors would like to thank Alistair Johnson and the PhysioNet team for helping to publicize the challenge and host the data.