Source note3 min read
Judge-dependent safety gains and model-specific helpfulness costs of evidence-sufficiency prompting in clinical LLMs
Source
arXiv
arxiv.org/abs/2607.18086v1
Source
- Source name: arXiv
- Source kind: paper
- Authors / organization: Koyar Afrasyab
- Venue: arXiv: cs.AI
- Published: 2026-07-20
- Collected: 2026-07-21
- URL: http://arxiv.org/abs/2607.18086v1
- PDF: https://arxiv.org/pdf/2607.18086v1
- DOI: UNKNOWN
Plain-Language Brief
A study investigates the impact of a structured evidence-sufficiency prompt on reducing unsafe overconfident answers from four different language models in a medical context. The study finds that the prompt significantly reduces unsafe overconfidence, but the reduction varies depending on the scoring judge. However, this reduction comes at a cost of decreased model helpfulness, especially for the model Gemini. The study suggests that the safety effects should be reported relative to human review and not as calibrated absolute rates.
What the Document Says
- A retrospective public-data benchmark was conducted using four language models (GPT-5.5, Claude Opus 4.8, Gemini 3.5 Flash, Grok 4.3) to evaluate the impact of a structured evidence-sufficiency prompt on reducing unsafe overconfidence.
- The primary judge (GPT-5.4-nano) found a significant reduction in unsafe overconfidence from 49.3% to 24.7%.
- The reduction was found to be judge-dependent, with the secondary judge (Claude Sonnet 5) nearly halving the effect.
- Blinded clinicians characterized the primary judge as a high-sensitivity and low-specificity screener, not a calibrated rate.
- The study found that the gain came at a model-specific helpfulness cost, with correct diagnosis decreasing significantly for all models but most notably for Gemini (-58 points).
- The study concludes that language model-judged clinical safety effects should be reported directionally and relatively, anchored to human review, and evaluated jointly with helpfulness.
Key Concepts Mentioned
- language models
- clinical context
- safety
- overconfidence
- evidence-sufficiency prompt
- judge dependency
- helpfulness
Claims Made by the Document
- The structured evidence-sufficiency prompt reduces unsafe overconfidence.
- The reduction in unsafe overconfidence varies depending on the scoring judge.
- There is a model-specific helpfulness cost associated with the reduction in unsafe overconfidence.
Evidence Used
- Unsafe overconfidence fell from 49.3% to 24.7%
- Magnitude was judge-dependent: Sonnet agreed on direction but nearly halved the effect (+13.1 points)
- The gain carried a model-specific helpfulness cost (correct diagnosis 80.3% to 50.3%)
Methods / Approach
UNKNOWN
Limitations Stated by the Authors
UNKNOWN
Limitations Noted by the Agent
Agent interpretation — not from the source.
UNKNOWN
Open Questions
UNKNOWN
Notes for Future Q&A
May include interpretation. Labeled where it does.
UNKNOWN
Raw Abstract / Excerpt
Background: LLM judges increasingly score whether clinical language models give overconfident answers under incomplete evidence, yet whether a measured 'safety gain' reflects real behavior change or the judge's calibration is unresolved. Using a structured evidence-sufficiency prompt as a test case, we asked whether it reduces unsafe overconfident answers, how far that effect depends on the scoring judge, and what it costs in helpfulness. Methods: In a retrospective public-data benchmark (Real-POCQi, HealthBench, MedRBench), four models (GPT-5.5, Claude Opus 4.8, Gemini 3.5 Flash, Grok 4.3) answered a fully paired common panel (1,200 cells) with a standard prompt and the wrapper. The pre-specified endpoint was the paired reduction in unsafe overconfidence scored by the primary judge (GPT-5.4-nano); secondary analyses added a different-family judge (Claude Sonnet 5), a correctness judge, matched scaffold controls, and a blinded three-clinician review. Results: Unsafe overconfidence fell from 49.3% to 24.7%, a paired reduction of 24.7 points (95% CI 21.8-27.7; p<0.001), robust in direction across models and paraphrases. Magnitude was judge-dependent: Sonnet agreed on direction but nearly halved the effect (+13.1 points), with one-directional disagreement. Blinded clinicians characterized the primary judge as a high-sensitivity (1.00), low-specificity (0.55) screen, not a calibrated rate. The gain carried a model-specific helpfulness cost (correct diagnosis 80.3% to 50.3%): near-free for GPT-5.5, near-total for Gemini (-58 points). Matched scaffold controls showed genuine behavior change, not judge circularity. Conclusions: LLM-judged clinical safety effects should be reported as directional and relative, anchored to human review and evaluated jointly with helpfulness, not as calibrated absolute rates. This does not establish clinical deployment readiness.
