DoctorRAG: Medical RAG Fusing Knowledge with Patient Analogy through Textual Gradients
Yuxing Lu, Gecheng Fu, Wei Wu, Xukai Zhao, Sin Yee Goi, Jinzhuo Wang
TL;DR
The paper tackles the high-stakes challenge of medical question answering by bridging explicit clinical knowledge with experiential, case-based reasoning. It introduces DoctorRAG, a retrieval-augmented generation framework that uses dual sources (knowledge bases and patient case repositories) together with declarative sentence transformations and ICD-10 tagging to improve retrieval precision. A novel multi-agent Med-TextGrad procedure iteratively refines outputs via textual gradients grounded in context and patient criteria, aiming for higher accuracy, relevance, and faithfulness. Extensive multilingual multitask experiments show DoctorRAG outperforms strong RAG baselines and demonstrates robust doctor-like reasoning across languages and tasks, marking a step toward clinically informed AI systems.
Abstract
Existing medical RAG systems mainly leverage knowledge from medical knowledge bases, neglecting the crucial role of experiential knowledge derived from similar patient cases -- a key component of human clinical reasoning. To bridge this gap, we propose DoctorRAG, a RAG framework that emulates doctor-like reasoning by integrating both explicit clinical knowledge and implicit case-based experience. DoctorRAG enhances retrieval precision by first allocating conceptual tags for queries and knowledge sources, together with a hybrid retrieval mechanism from both relevant knowledge and patient. In addition, a Med-TextGrad module using multi-agent textual gradients is integrated to ensure that the final output adheres to the retrieved knowledge and patient query. Comprehensive experiments on multilingual, multitask datasets demonstrate that DoctorRAG significantly outperforms strong baseline RAG models and gains improvements from iterative refinements. Our approach generates more accurate, relevant, and comprehensive responses, taking a step towards more doctor-like medical reasoning systems.
