如何在2026年构建和评估医疗聊天机器人

The medical chatbot demos cleanly. You ask about hypertension management; it cites a 2024 AHA guideline with a quoted span. You ask about a chest-tightness episode that started forty minutes ago and it answers as if the question were educational. Two days into pilot the on-call cardiologist forwards the transcript to compliance. The chatbot is pulled within the week.

医疗聊天机器人的演示效果很好。你询问高血压管理；它会引用2024年AHA指南并附上引用的文本片段。你询问四十分钟前开始的胸闷发作，它却像回答教育问题一样作答。试点开始两天后，值班心脏病专家将对话记录转发给了合规部门。该聊天机器人在一周内就被撤下了。

Most posts on this would call it a hallucination problem and pitch a Groundedness rubric. That misses the failure mode. Groundedness was fine. The model grounded its answer in a real, relevant guideline. The failure was that the question was never the bot’s to answer.

关于此问题的大多数文章都会将其称为幻觉问题，并推崇Groundedness评分标准。但这忽略了故障模式。Groundedness本身没问题。模型将其回答基于真实且相关的指南。失败之处在于，这个问题根本不该由机器人来回答。

The opinion this post earns: a medical chatbot is a refusal engine first and an answer engine second. The primary metric is not “what fraction did it answer correctly.” It is a confusion matrix on refusal. What fraction of unsafe-to-answer questions did it correctly refuse, and what fraction of safe questions did it unnecessarily refuse? Generation rubrics matter, but they score the answerable subset only. Get the refusal taxonomy wrong and your Groundedness chart is decoration.

本文的核心观点是：医疗聊天机器人首先是一个拒绝引擎，其次才是一个回答引擎。主要指标不是“它正确回答了多少比例的问题”。它是关于拒绝的混淆矩阵。它正确拒绝了多少比例的不安全（不宜回答）问题，又错误拒绝了多少比例的安全问题？生成评估标准很重要，但它们只对可回答的子集进行评分。如果把拒绝分类法搞错了，你的Groundedness图表就只是摆设。

This guide is the working playbook: taxonomy first, structured output with refusal as a first-class response type, inline PHI guardrails, eval suite split by failure family, confusion matrix gated in CI, same rubrics on live OTel spans. Code shaped against the ai-evaluation SDK and traceAI. Scope: educational and triage-routing chatbots only; anything that diagnoses, doses, or interprets specific clinical data may be regulated under FDA SaMD rules. Get counsel before scoping.

本指南是操作手册：首先是分类法，将拒绝作为一等响应类型的结构化输出，内联 ...