Evaluating Web Retrieval–Assisted Large Language Models With and Without Whitelisting for Evidence-Based Neurology: Comparative Study

Restricting retrieval to authoritative neurology domains yielded a clinically meaningful 8 to 18 percentage-point gain in correctness and halved output variability, upgrading a consumer search assistant to a decision-support-level tool that at least performed on par with a specialized literature engine. Lightweight source control is therefore a pragmatic safety lever for maintaining continuously updated, web-based RAG-augmented LLMs fit for evidence-based neurology.