Maps to
QMSR / ISO 13485: §820.30(f)
ISO 13485: §7.3.6
IEC 62366: §5.7
Requirement text
The manufacturer shall plan both formative and summative usability evaluation activities. The evaluation plan must specify the evaluation methods, participant criteria, settings, and how results will be analyzed. Summative evaluation planning must ensure coverage of all hazard-related use scenarios.
What changed
IEC 62366-1:2015 replaced the 2007 first edition with a major restructuring. The standard was split into Part 1 (normative requirements) and Part 2 (IEC TR 62366-2, informative guidance and methods). The scope broadened to include hazards of all types including psychological hazards, not just direct physical hazards.
The standard introduced a formative/summative evaluation framework not present in 2007. The 2007 requirement to identify primary operating functions was removed — instead, the 2015 version mandates identification and evaluation of hazard-related use scenarios. A concept of User Interface of Unknown Provenance (UOUP) was added, allowing simplified evaluation for legacy or off-the-shelf interfaces based on post-market data.
Amendment 1 (2020) further refined the standard: it updated the ISO 14971 reference to the 2019 edition, introduced bidirectional exchange between risk management and usability engineering (previously one-directional), added training as a third priority risk control measure alongside information for safety, introduced the concept of 'use difficulty' (close calls and observed problems that don't result in actual use errors), and replaced 'action error' with 'physical mismatch' to encourage broader analysis of use problems.
Atomic constraints
- •A Usability Evaluation Plan must be documented before evaluations begin.
- •The plan must describe formative evaluation methods and their schedule.
- •The summative evaluation plan must specify the user profile for test participants.
- •All hazard-related use scenarios must be covered by summative evaluation test cases.
- •The plan must specify a minimum number of test participants and the test setting.
- •The plan must describe how use errors and hazards observed during testing will be analyzed.
Common gaps
Formative evaluation used to skip summative testing
majorCompanies mistakenly believe they can skip summative testing by only doing formative evaluations. While you can reduce scope by leveraging data from a predicate device (Clause 5.10), you must provide a technical rationale explaining why design changes do not affect previously validated critical tasks. Without this rationale, summative evaluation is required.
Evidence signals
- •
FILE_EXISTS
Usability.*Evaluation.*Plan|Usability.*Plan|Usability.*Test.*Plan
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CONTENT_MATCH
Does this document plan both formative and summative usability evaluation activities, specifying participant criteria matching the intended user profile, test methods, settings, and confirming that all hazard-related use scenarios are covered by test cases?
Audit defense
The Usability Evaluation Plan for [your product] (Doc ID: [your document ID]) documents the formative evaluation schedule and summative evaluation design, including participant criteria, test setting, and a traceability matrix confirming that all hazard-related use scenarios are covered by summative test cases.