Disparities in Multilingual LLM-Based Healthcare Q&A

TL;DR

This paper investigates disparities in multilingual healthcare Q&A using LLMs, revealing significant cross-lingual differences in information coverage and factual accuracy, and explores methods to improve equitable knowledge alignment.

Contribution

It introduces a multilingual healthcare dataset, analyzes cross-lingual disparities in LLM responses, and demonstrates how contextual information can enhance factual alignment across languages.

Findings

LLMs favor English Wikipedia responses over other languages.

Providing contextual excerpts improves factual alignment with culturally relevant knowledge.

Significant disparities exist in healthcare information coverage across languages.

Abstract

Equitable access to reliable health information is vital when integrating AI into healthcare. Yet, information quality varies across languages, raising concerns about the reliability and consistency of multilingual Large Language Models (LLMs). We systematically examine cross-lingual disparities in pre-training source and factuality alignment in LLM answers for multilingual healthcare Q&A across English, German, Turkish, Chinese (Mandarin), and Italian. We (i) constructed Multilingual Wiki Health Care (MultiWikiHealthCare), a multilingual dataset from Wikipedia; (ii) analyzed cross-lingual healthcare coverage; (iii) assessed LLM response alignment with these references; and (iv) conducted a case study on factual alignment through the use of contextual information and Retrieval-Augmented Generation (RAG). Our findings reveal substantial cross-lingual disparities in both Wikipedia coverage and LLM factual alignment. Across LLMs, responses align more with English Wikipedia, even when the prompts are non-English. Providing contextual excerpts from non-English Wikipedia at inference time effectively shifts factual alignment toward culturally relevant knowledge. These results highlight practical pathways for building more equitable, multilingual AI systems for healthcare.