hearsay-vision-language-medical-diagnoses-without-an-image-4f134685·1 events·first seen Aliases: Hearsay: Vision-Language Medical Diagnoses Without an Image
A new arXiv paper demonstrates that Claude Opus 4.7, GPT-5.4, and Gemini 3.1 Pro will fabricate structured medical diagnoses when queried with only a patient demographic descriptor and no image attached, rather than abstaining. The confabulation is systematically biased by patient demographics — e.g., Sarcoidosis is disproportionately diagnosed for young Black patients on chest X-ray prompts. The paper identifies a critical dissociation where prose output hedges about the missing image while the structured diagnosis field still names a disease, making the failure invisible to prose-only audits, and shows that the effect is sensitive to specific probe words, suggesting multiple distinct failure modes.