On the Compositional Generalization of Multimodal LLMs for Medical
  Imaging
Authors: name: Zhenyang Cai, name: Junying Chen, name: Rongsheng Wang, name: Weihong Wang, name: Yonglin Deng, name: Dingjie Song, name: Yize Chen, name: Zixu Zhang, name: Benyou Wang

Multimodal large language models (MLLMs) hold significant potential in the
medical field, but their capabilities are often limited by insufficient data in
certain medical domains, highlighting the need for understanding what kinds of
images can be used by MLLMs for generalization. Current research suggests that
multi-task training outperforms single-task as different tasks can benefit each
other, but they often overlook the internal relationships within these tasks,
providing limited guidance on selecting datasets to enhance specific tasks. To
analyze this phenomenon, we attempted to employ compositional generalization
(CG)-the ability of models to understand novel combinations by recombining
learned elements-as a guiding framework. Since medical images can be precisely
defined by Modality, Anatomical area, and Task, naturally providing an
environment for exploring CG. Therefore, we assembled 106 medical datasets to
create Med-MAT for comprehensive experiments. The experiments confirmed that
MLLMs can use CG to understand unseen medical images and identified CG as one
of the main drivers of the generalization observed in multi-task training.
Additionally, further studies demonstrated that CG effectively supports
datasets with limited data and delivers consistent performance across different
backbones, highlighting its versatility and broad applicability. Med-MAT is
publicly available at https://github.com/FreedomIntelligence/Med-MAT.