When Clinical Software Becomes a Regulated Device

当临床软件成为受监管的医疗器械时

Whether your clinical software is a regulated medical device is decided by what you claim it does, not by how it is built. The same model can be an unregulated administrative tool with one intended-use statement and a class III device with another, and the statement is yours to write. 你的临床软件是否属于受监管的医疗器械，取决于你声称它具有什么功能，而不是它如何构建。同一个模型，如果预期用途声明不同，既可以是不受监管的行政工具，也可以是三类医疗器械，而这份声明需要由你来撰写。

Information, not legal advice, and not clinical or regulatory advice. Reviewed 4 August 2026. Device classification is fact-specific and the consequences of getting it wrong include enforcement action and product withdrawal. Use a regulatory professional. This page describes the questions that decide the answer; it does not answer them for your product. 本文仅供参考，不构成法律建议，也不构成临床或监管建议。最后审阅日期：2026年8月4日。器械分类具有高度的事实特定性，分类错误的后果包括执法行动和产品下架。请咨询监管专业人士。本页面描述了决定分类结果的问题，但并未针对你的具体产品给出答案。

The line, in one paragraph per jurisdiction

各司法管辖区的界限（每段一个）

European Union. Software is a medical device if the manufacturer intends it for a medical purpose — diagnosis, prevention, monitoring, prediction, prognosis, treatment or alleviation of disease — as set out in the definition in Regulation (EU) 2017/745, the Medical Device Regulation, or the corresponding definition in the In Vitro Diagnostic Regulation (EU) 2017/746 where it works on specimens. There is no clinical decision support carve-out. Software that drives or influences the use of a device, or provides information used to take decisions for diagnostic or therapeutic purposes, is in. 欧盟。 如果制造商旨在将软件用于医疗目的（即疾病的诊断、预防、监测、预测、预后、治疗或缓解），则该软件属于医疗器械。这符合欧盟第2017/745号条例（《医疗器械条例》，MDR）中的定义，或在处理样本时符合《体外诊断医疗器械条例》（EU）2017/746中的相应定义。欧盟没有针对临床决策支持（CDS）的豁免条款。凡是驱动或影响器械使用，或提供用于诊断或治疗决策信息的软件，均被纳入监管范围。

United States. Software is a device under the Federal Food, Drug, and Cosmetic Act if it is intended for use in the diagnosis, cure, mitigation, treatment or prevention of disease — but section 520(o), added by the 21st Century Cures Act in 2016, excludes certain clinical decision support software from the device definition entirely, on four cumulative conditions. That carve-out has no EU equivalent and it is the single biggest structural difference between the two regimes. 美国。 根据《联邦食品、药品和化妆品法案》，如果软件旨在用于疾病的诊断、治愈、缓解、治疗或预防，则属于医疗器械。但2016年《21世纪治愈法案》新增的第520(o)条，在满足四个累积条件的情况下，将某些临床决策支持软件完全排除在器械定义之外。这种豁免在欧盟没有对应条款，这是两个监管体系之间最大的结构性差异。

EU: qualification then classification

欧盟：先定性，后分类

Two questions in order. Qualification asks whether it is a device at all. Classification asks which class, which determines the conformity assessment route and whether a notified body is involved. 按顺序回答两个问题。定性（Qualification）旨在确定它是否属于医疗器械；分类（Classification）旨在确定其类别，这决定了合格评定路径以及是否需要公告机构（Notified Body）介入。

Qualification: Is it software? A set of instructions processing input data and creating output data. Does it perform an action on data beyond storage, archival, communication or simple search? A viewer that displays an image unchanged is not a device; one that segments the image is performing an action. Is the action for the benefit of an individual patient? Software that produces population-level epidemiological output for research is treated differently from software that produces a result about a named patient. Does the manufacturer intend a medical purpose? This is decided from your intended purpose statement, labelling, instructions for use and promotional material. Marketing copy is evidence of intended purpose, which is why regulatory teams read it. The MDCG guidance on qualification and classification of software (MDCG 2019-11) is the working document for this analysis, and it predates the current wave of AI products but is still the reference European regulators apply. 定性： 它是软件吗？即处理输入数据并创建输出数据的一组指令。它是否对数据执行了存储、归档、通信或简单搜索之外的操作？仅显示图像而不做改变的查看器不是医疗器械；而对图像进行分割的查看器则执行了操作。该操作是否为了特定患者的利益？用于研究的群体流行病学输出软件与针对特定患者产生结果的软件处理方式不同。制造商是否有医疗目的？这取决于你的预期用途声明、标签、使用说明和宣传材料。营销文案是预期用途的证据，这就是为什么监管团队会阅读它们的原因。MDCG关于软件定性和分类的指南（MDCG 2019-11）是进行此项分析的工作文件，虽然它早于当前的AI产品浪潮，但仍是欧洲监管机构应用的参考标准。

Classification: Software that qualifies is classified under the MDR’s classification rules in Annex VIII, and Rule 11 is the one that governs software intended to provide information used to take decisions for diagnostic or therapeutic purposes. The structure of Rule 11 is that such software is class IIa by default; class IIb if the decisions could cause serious deterioration of health or surgical intervention; and class III if they could cause death or an irreversible deterioration of health. Software intended to monitor physiological processes is class IIa, or IIb where the parameters monitored are such that variation could result in immediate danger. Everything else is class I. The practical effect of Rule 11 is that almost no diagnostic AI is class I, and anything above class I needs a notified body. Notified body capacity has been a constraint on the European market since the MDR applied, and that is a scheduling reality rather than a compliance one. 分类： 符合条件的软件根据MDR附件VIII中的分类规则进行分类。第11条规则专门管理旨在提供用于诊断或治疗决策信息的软件。第11条的结构规定：此类软件默认为IIa类；如果决策可能导致严重的健康恶化或需要手术干预，则为IIb类；如果可能导致死亡或不可逆转的健康恶化，则为III类。旨在监测生理过程的软件为IIa类，如果监测参数的变化可能导致直接危险，则为IIb类。其他所有软件均为I类。第11条的实际影响是，几乎没有诊断类AI属于I类，任何高于I类的产品都需要公告机构介入。自MDR实施以来，公告机构的承载能力一直是欧洲市场的一个制约因素，这是一个进度安排上的现实，而非合规性问题。

US: the device definition and the CDS carve-out

美国：器械定义与临床决策支持（CDS）豁免

The four conditions of the clinical decision support exclusion are cumulative — fail one and the software is a device. Paraphrasing the statute: 临床决策支持豁免的四个条件是累积的——只要不满足其中任何一个，该软件即被视为医疗器械。法条释义如下：

It is not intended to acquire, process or analyse a medical image or a signal from an in vitro diagnostic device or a signal acquisition system. Failing this one is common and immediate: anything working on imaging or waveform data is out of the carve-out at step one.
它不旨在获取、处理或分析医学图像，或来自体外诊断设备或信号采集系统的信号。这一点通常很难满足：任何处理成像或波形数据的软件在第一步就被排除在豁免之外。
It is intended to display, analyse or print medical information about a patient or other medical information such as peer-reviewed clinical studies and clinical practice guidelines.
它旨在显示、分析或打印关于患者的医疗信息，或其他医疗信息（如经同行评审的临床研究和临床实践指南）。
It is intended to support or provide recommendations to a health care professional about prevention, diagnosis or treatment.
它旨在支持或向医疗保健专业人员提供关于预防、诊断或治疗的建议。
It is intended to enable the professional to independently review the basis for the recommendations, so that they do not rely primarily on any of them.
它旨在使专业人员能够独立审查建议的依据，从而不主要依赖于这些建议中的任何一项。

The fourth condition is where most AI products fail, and it is worth being blunt about why. A model that outputs a score without an inspectable basis does not enable independent review. FDA’s guidance on the exclusion, finalised in September 2022, took a narrow view: the software should explain the basis, identify the inputs and the relevant sources, and be presented so the professional can reach their own conclusion rather than accept the output. “Explainable enough for a clinician to disagree with” is a good working restatement, and it is a product requirement with a regulatory consequence attached. Note also that the carve-out is only for software supporting health care professionals. Software providing recommendations to patients or caregivers is not within it. 第四个条件是大多数AI产品失败的地方，值得直言其原因。一个输出分数却无法检查依据的模型，无法实现独立审查。FDA于2022年9月最终确定的关于豁免的指南采取了狭义的观点：软件应解释依据、识别输入内容和相关来源，并以一种让专业人员能够得出自己的结论而非直接接受输出结果的方式呈现。“足以让临床医生提出异议的可解释性”是一个很好的工作重述，这既是产品需求，也带有监管后果。此外请注意，该豁免仅适用于支持医疗保健专业人员的软件。向患者或护理人员提供建议的软件不在此豁免范围内。

US pathways, and what most AI devices use

美国监管路径及大多数AI器械的选择

510(k) premarket notification: Demonstrate substantial equivalence to a legally marketed predicate device. The route the large majority of AI-enabled devices have taken. Requires a predicate, which is why the first device of a kind cannot use it.
510(k)上市前通知： 证明与合法上市的同类产品（Predicate Device）具有实质等同性。这是绝大多数AI赋能设备所采取的路径。它需要一个同类产品作为参照，这就是为什么首创类设备无法使用此路径的原因。
De Novo classification: For a novel device…
De Novo分类： 针对创新型器械……