Advancing Healthcare Automation: Multi-Agent System for Medical Necessity Justification
Himanshu Pandey, Akhil Amod, Shivang
TL;DR
This work tackles the healthcare PA bottleneck by introducing a multi-agent system of specialized LLMs that split the medical-necessity determination into leaf-level checks and bottom-up aggregation. The leaf-stage uses retrieval-augmented evidence selection, evidence classification, and jury-style voting to output item judgments with explanations, while a Propagator Agent performs logical-operator based parent-node fusion to yield a final root decision. Across MIMIC-III-based data and clinical guidelines, GPT-4 emerges as the strongest performer, achieving approximately $86.2\%$ leaf-item accuracy and $95.6\%$ root-checklist accuracy, with CoT prompting and ICL enhancing performance for smaller models. The study also emphasizes explainability through evidenced rationales and chain-of-thought prompts, and outlines a scalable, microservice-architecture path toward deployable PA automation and broader clinical decision-support applications.
Abstract
Prior Authorization delivers safe, appropriate, and cost-effective care that is medically justified with evidence-based guidelines. However, the process often requires labor-intensive manual comparisons between patient medical records and clinical guidelines, that is both repetitive and time-consuming. Recent developments in Large Language Models (LLMs) have shown potential in addressing complex medical NLP tasks with minimal supervision. This paper explores the application of Multi-Agent System (MAS) that utilize specialized LLM agents to automate Prior Authorization task by breaking them down into simpler and manageable sub-tasks. Our study systematically investigates the effects of various prompting strategies on these agents and benchmarks the performance of different LLMs. We demonstrate that GPT-4 achieves an accuracy of 86.2% in predicting checklist item-level judgments with evidence, and 95.6% in determining overall checklist judgment. Additionally, we explore how these agents can contribute to explainability of steps taken in the process, thereby enhancing trust and transparency in the system.
