The short answer
Design verification asks: did we build the device right? It confirms that design outputs meet design inputs. Design validation asks: did we build the right device? It confirms that the finished device meets user needs and its intended use.
The ISO 9000:2015 definitions make the distinction precise. Verification is “confirmation, through the provision of objective evidence that specified requirements have been fulfilled.” Validation is confirmation “that the requirements for a specific intended use or application have been fulfilled” (as quoted by BSI).
| Design verification | Design validation | |
|---|---|---|
| Question | Did outputs meet inputs? | Does the device meet user needs and intended use? |
| ISO 13485:2016 clause | 7.3.6 | 7.3.7 |
| Typical evidence | Bench tests, inspections, analyses, software unit and integration tests | Clinical evaluation, simulated or actual use testing, human factors validation, software validation |
| Product used | Prototypes or production-equivalent units | ”Representative product,” including “initial production units, batches or their equivalents” (BSI) |
| Timing | Throughout development | ”Must be completed prior to release” (FDA) |
For a deeper look at verification methods and sample sizes, see Design Verification for Medical Devices: Requirements, Methods and Common FDA Findings. For a deeper look at validation, including human factors and clinical evidence, see Design Validation for Medical Devices: User Needs, Human Factors and Clinical Evidence.
What FDA expects under QMSR
Since February 2, 2026, FDA’s Quality Management System Regulation incorporates ISO 13485:2016. In its QMSR design and development training, FDA summarizes the two clauses this way (FDA, Tartal):
- 7.3.6 verification: performed “per documented plans and procedures to ensure outputs meet inputs,” and “The verification plans, including methods, acceptance criteria, and statistical techniques must be documented.”
- 7.3.7 validation: performed “per documented plans and procedures to ensure the device meets its intended use,” conducted “on representative product,” and completed “prior to release.”
The old QSR wording is still a useful benchmark. Former § 820.30(g) required validation “under actual or simulated use conditions” and said it “shall include software validation and risk analysis, where appropriate” (LII).
What changed in 2026
- The 1997 Design Control Guidance was withdrawn. FDA’s withdrawn guidance list shows the March 1997 guidance withdrawn on February 2, 2026, the day QMSR took effect (FDA). Its familiar “waterfall” diagram is no longer current FDA guidance.
- Verification and validation are explicit inspection elements. CP 7382.850 lists “Design and Development Verification,” “Design and Development Validation” and “Design and Development Software Validation” as elements of the design and development area (FDA CP 7382.850).
- Design controls remain a top enforcement issue. In FY2025, design control deficiencies ranked second in device warning letters, with 25 (ECA Academy).
- Human factors guidance was updated. FDA finalized “Content of Human Factors Information in Medical Device Marketing Submissions” in May 2026 (Federal Register), and revised its core human factors guidance in August 2026 to align with QMSR, ISO 14971 and IEC 62366-1 (FDA; Emergo by UL).
Design verification checklist
- A verification plan exists with methods, acceptance criteria and statistical rationale for sample sizes
- Every design input has at least one verification activity linked to it
- Test methods are validated or justified, and test equipment is calibrated
- Results are recorded against pre-defined acceptance criteria, including failures and retests
- Risk control measures are verified for implementation and effectiveness
- Software verification covers unit, integration and system testing, traced to software requirements
- Verification is repeated or justified after any design change
Design validation checklist
- A validation plan defines user needs, intended use, users and use environments
- Validation is performed on representative product: initial production units, batches or equivalents, with equivalence justified
- Testing covers actual or simulated use conditions
- Human factors validation follows FDA’s current human factors guidance and IEC 62366-1
- Software validation is complete for device software functions
- Clinical evaluation or clinical data supports the intended use claims
- Residual risks are evaluated as acceptable before release
- Validation is completed before release, with results in the design and development file
Linking it all: the traceability matrix
Verification and validation only prove something when they are traced. A practical matrix links each row across:
| User need | Design input | Design output | Verification | Validation | Risk control |
|---|---|---|---|---|---|
| Nurse can set dose in under 30 s | UI-012: dose entry in ≤3 steps | SW spec 4.2, UI design v3 | TR-101 usability bench test | HF-VAL-01 summative study | RC-07 confirmation screen |
The row above is illustrative. FDA’s own design training notes that design plans should “Note roles and responsibilities, traceability methods, and resources needed” (FDA, Tartal).
Checking V&V evidence at scale
Most V&V gaps are not missing tests. They are tests that do not link back to an input, acceptance criteria written after the fact, or validation run on units that are not representative. Finding them means reading the whole design file.
AI document assessment can read verification and validation plans and reports against ISO 13485 clauses 7.3.6 and 7.3.7, flag inputs with no linked test and cite the passage behind every finding. Run a sample regulatory document assessment on one V&V plan. AskDona shows the evidence; your engineers decide.
FAQ
What is the difference between design verification and validation? Verification confirms design outputs meet design inputs. Validation confirms the device meets user needs and its intended use.
Does validation have to use production units? ISO 13485 requires validation on representative product, which includes “initial production units, batches or their equivalents” (BSI).
Is FDA’s 1997 Design Control Guidance still valid? No. FDA withdrew it on February 2, 2026 (FDA).
Is human factors testing part of validation? Yes, for devices where use errors could cause harm. FDA updated its human factors guidance in 2026 (FDA).
References
All pages opened and checked by October 9, 2026.
| Source | Type | Date | Used for |
|---|---|---|---|
| FDA: QMSR – Design and Development (Tartal) | Regulator training | 2026 | Clauses 7.3.6, 7.3.7 |
| BSI: Validation and verification webinar | Certification body | Nov 9, 2016 | ISO 9000 definitions, representative product |
| LII: former 21 CFR 820.30 | Regulation text (historical) | Pre-2026 | QSR validation wording |
| FDA: Withdrawn guidance list | Regulator | 2026 | 1997 guidance withdrawn |
| FDA: CP 7382.850 | Regulator | Feb 2, 2026 | V&V inspection elements |
| ECA Academy: FY2025 device warning letters | Industry analysis | Feb 2026 | Design controls #2 |
| Federal Register: HF content guidance | Regulator | May 29, 2026 | HF submissions |
| FDA: Applying Human Factors guidance | Regulator guidance | Aug 2026 | HF update |
| Emergo by UL: HF guidance update | Consultancy | Aug 5, 2026 | Alignment with QMSR |