Perspectives on Cross-Lingual Consistency in LLMs for Medical Questions

Minh Duc Bui, Mario Sanz-Guerrero, Abteen Ebrahimi, Sagi Shaier, Peter Herbert Kann, Manuel Mager, Katharina von der Wense


Abstract
Should multilingual LLMs answer medical questions consistently across input languages, or adapt responses to cultural cues? Existing multilingual medical benchmarks usually assume that medically correct answers should remain consistent across languages and treat cross-lingual variation as model error. In contrast, cultural adaptation research argues that appropriate medical answers may legitimately differ across contexts. We review the multilingual medical NLP literature through these two perspectives, we identify three gaps: limited stakeholder perspectives (e.g., of medical professionals), a lack of empirical evidence on which approach better serves users, and no benchmarks capable of distinguishing universally correct from culture-specific cases. To address the first gap, we survey 356 participants across three stakeholder groups (medical, NLP, and anthropology professionals) in three countries (Germany, Spain, and the United States). Anthropologists consistently favor adaptation, while medical and NLP respondents remain divided, with notable divergence between U.S. and European medical professionals. LLMs prompted with profession and country personas fail to reproduce this variation, overestimating cross-lingual consistency preference among NLP and medical personas. We conclude that neither consistency nor adaptation can currently be considered clearly preferable, highlighting the need for empirical evidence on which approach better serves users across cultural contexts.
Anthology ID:
2026.emnlp-main.2106
Volume:
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
EMNLP
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
47934–47948
Language:
URL:
https://aclanthology.org/2026.emnlp-main.2106/
DOI:
Bibkey:
Cite (ACL):
Minh Duc Bui, Mario Sanz-Guerrero, Abteen Ebrahimi, Sagi Shaier, Peter Herbert Kann, Manuel Mager, and Katharina von der Wense. 2026. Perspectives on Cross-Lingual Consistency in LLMs for Medical Questions. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing, pages 47934–47948, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Perspectives on Cross-Lingual Consistency in LLMs for Medical Questions (Bui et al., EMNLP 2026)
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PDF:
https://aclanthology.org/2026.emnlp-main.2106.pdf