Software Verification and Validation for Medical Devices: What Teams Need to Know

For medical device companies developing softPostsware-driven products, verification and validation (V&V) often feels like navigating a maze of regulatory requirements, testing protocols, and documentation demands. Yet V&V represents far more than a compliance checkbox, it's the systematic process that demonstrates your software does what it's supposed to do and actually meets user needs in real-world clinical settings.

Whether you're building standalone Software as a Medical Device (SaMD) or embedded software for a diagnostic instrument, understanding how to structure V&V activities can mean the difference between a smooth FDA submission and months of costly delays. This guide breaks down what teams need to know about software V&V, from planning through submission-ready documentation.

What Does the FDA Expect from Software V&V?

The FDA's guidance on software validation emphasizes that verification and validation are distinct but complementary activities throughout the software development lifecycle. Understanding this distinction is fundamental to building an effective V&V strategy.

Verification answers the question: "Are we building the product right?" It confirms that software outputs from each development phase meet the inputs and requirements for that phase. Verification activities include code reviews, unit testing, integration testing, and requirements traceability. You're essentially checking that the implementation matches the design specifications.

Validation addresses: "Are we building the right product?" It ensures the final software product meets user needs and intended use requirements in the actual environment where it will be deployed. Validation happens at the system level and includes activities like user acceptance testing, clinical validation studies, and human factors validation.

The FDA's expectations for V&V rigor scale with software risk classification. For Class III devices or moderate-risk Class II software, expect comprehensive documentation including detailed test protocols, traceability matrices linking requirements to tests, and formal validation reports. Lower-risk devices may warrant a more streamlined approach, but the fundamental V&V principles remain constant.

IEC 62304, the international standard for medical device software lifecycle processes, provides the framework most teams follow. The standard requires V&V planning before development begins, defines specific activities for each software safety class, and mandates traceability throughout. FDA reviewers increasingly expect submissions to demonstrate IEC 62304 compliance, making it the de facto roadmap for medical device software development.

How V&V Fits into the IEC 62304 Software Lifecycle

IEC 62304 structures software development into distinct phases, each with corresponding V&V activities that build upon one another. Understanding this progression helps teams plan resources and avoid the common trap of treating V&V as an afterthought.

Planning Phase: Before writing a single line of code, you'll develop your Software Development Plan and Software Verification and Validation Plan. These documents define your development approach, V&V strategy, risk management activities, and documentation standards. The V&V plan specifies which verification methods you'll use (code reviews, static analysis, unit tests), validation approaches (system testing, user studies), and acceptance criteria for each phase.

Requirements Phase: Software requirements must be verified to ensure they're complete, unambiguous, and testable. Verification activities include requirements reviews, traceability to system requirements and risk controls, and establishing test conditions. This is where you create your traceability matrix that will follow the product through submission.

Architectural and Detailed Design Phase: Design verification confirms that your architecture addresses all requirements and that detailed designs correctly implement the architecture. Activities include design reviews, interface verification, and SOUP (Software of Unknown Provenance) evaluation for third-party components.

Implementation Phase: Unit-level verification happens during coding through peer reviews, static code analysis, and unit testing. For higher safety classes, you'll need documented evidence of these activities with defect tracking and resolution. Integration testing verifies that software units work together correctly according to the architectural design.

System Testing Phase: This is where verification transitions into validation. System testing verifies that integrated software meets all software requirements. System validation demonstrates that the complete medical device (software plus hardware if applicable) meets user needs and intended use requirements in representative conditions.

Throughout each phase, you're building a documentation trail that demonstrates systematic development and risk management, which is exactly what FDA reviewers need to see during premarket review.

Practical V&V Activities for SaMD vs Embedded Software

While V&V principles apply universally to medical device software, practical implementation differs significantly between standalone Software as a Medical Device and embedded software systems.

SaMD V&V Considerations: For cloud-based diagnostic tools, mobile health applications, or clinical decision support software, your V&V strategy must address cybersecurity, interoperability, and diverse deployment environments. Testing includes validating software across multiple operating systems, browsers, or mobile platforms. Network security testing, data encryption verification, and authentication/authorization testing become critical verification activities. You'll need documented evidence that the software performs consistently across all claimed environments and maintains data integrity throughout the intended workflow.

Performance testing takes on added importance for SaMD, you're not just verifying algorithmic accuracy but also demonstrating acceptable response times, scalability under realistic patient loads, and graceful handling of network disruptions or data anomalies.

Embedded Software V&V: For software embedded in medical devices like infusion pumps, imaging systems, or patient monitors, V&V must account for hardware-software integration, real-time performance requirements, and often safety-critical failure modes. Hardware-in-the-loop testing verifies that software correctly controls physical actuators and processes sensor inputs. Timing analysis confirms that real-time software meets deadline requirements. Failure mode testing validates that software responds appropriately to hardware faults, power interruptions, or environmental conditions.

Regardless of software type, risk-based testing depth is essential. IEC 62304 defines three software safety classes (A, B, C) based on the potential for software failure to result in harm. Class C software requires the most rigorous V&V, including complete requirements traceability, comprehensive unit testing, and extensive system validation. Class A software, where failure cannot contribute to a hazardous situation, allows a more streamlined approach focused on system-level validation.

Your test strategy should explicitly tie test depth and methods to risk analysis. High-risk software functions demand more exhaustive testing, boundary condition analysis, and fault injection testing. Lower-risk features can be verified through sampling or reduced test cases, provided your rationale is documented.

How We Document V&V for FDA and CE Submissions

FDA and Notified Body reviewers need clear evidence that your V&V activities were planned, executed systematically, and demonstrated acceptable results. This documentation forms a critical component of your 510(k), De Novo, PMA, or CE technical file.

Test Protocols: Before executing V&V activities, you'll create test protocols that specify test objectives, test configurations, test cases with expected results, pass/fail criteria, and procedures. Protocols should be reviewed and approved before testing begins. Each test case traces back to specific requirements, creating the bidirectional traceability that regulators expect.

Test Reports: After test execution, formal test reports document test results, any deviations or anomalies observed, defect tracking, and final acceptance conclusions. Reports must be signed by appropriate personnel, typically the test engineer and quality representative. Any test failures require documented investigation, corrective action, and confirmation of resolution through retesting.

Traceability Matrices: Perhaps the most critical V&V documentation, traceability matrices link system requirements to software requirements, software requirements to design elements, design elements to source code modules, and requirements to verification tests and validation activities. This web of traceability demonstrates that every requirement has been implemented and verified, and that every test traces to specific requirements. Modern tools can automate much of this traceability, but the relationships must be carefully maintained as requirements evolve.

Defect Management: All defects discovered during V&V must be logged, classified by severity, investigated for root cause, and tracked through resolution. Your defect management process demonstrates that issues were systematically addressed and that fixes were verified effective without introducing new problems. Regulatory submissions typically include defect summaries showing types of defects found, resolution approaches, and any known anomalies or limitations in the released software.

Software Version Documentation: Your V&V documentation package must clearly identify which software version was validated, including version control information, configuration management records, and SOUP/OTS component versions. This enables regulators to understand exactly what was tested and confirmed.

For 510(k) submissions, this V&V documentation typically appears in the Software Description Document or as supporting documentation demonstrating substantial equivalence. For CE marking, the technical file must include comprehensive V&V documentation as evidence of conformity to essential requirements and harmonized standards.

Common V&V Mistakes in MedTech Startups (and How to Avoid Them)

Even experienced medical device teams encounter predictable V&V pitfalls that can derail submissions or create expensive remediation cycles. Here are the most common mistakes and practical strategies to avoid them.

Starting V&V Too Late: The most costly mistake is treating V&V as a post-development activity. When teams build software first and then try to retrofit V&V documentation, they discover untested requirements, missing traceability, and insufficient verification evidence. Instead, establish your V&V plan before development begins, create test cases alongside requirements, and verify incrementally throughout development.

Inadequate Requirements Traceability: Losing track of the relationships between requirements, design, code, and tests creates massive problems during submission preparation. Implement traceability from day one using tools or rigorous documentation practices, and maintain it as requirements evolve. Every requirement change should trigger evaluation of affected design, code, and tests.

Insufficient Test Coverage Documentation: Running tests isn't enough, you must document test coverage and demonstrate that coverage is appropriate for the software's risk classification. For Class B and C software, expect reviewers to scrutinize whether your testing adequately addresses high-risk functions, edge cases, and failure modes. Maintain coverage metrics and document rationale for areas with reduced testing.

Weak Validation Evidence: Verification alone isn't sufficient. FDA reviewers want to see that you validated software with representative users in realistic conditions that approximate the intended use environment. This doesn't always require full clinical studies, but you need documented evidence that the software meets user needs. User acceptance testing, formative usability studies, or validation studies with clinical partners provide this evidence.

Inadequate SOUP Management: Third-party libraries, open-source components, and commercial off-the-shelf software require specific V&V attention. Teams often fail to adequately document SOUP identification, evaluate SOUP risks, verify SOUP functionality, and maintain SOUP configuration records. Create a SOUP inventory early, assess each component's risk contribution, and verify that SOUP functions critical to your device work correctly.

Poor Change Management: As software evolves through development and after initial release, V&V must address changes systematically. Implement regression testing strategies, maintain impact analysis for changes, and update V&V documentation to reflect the current software version. FDA increasingly scrutinizes whether post-market software updates have been adequately validated.

At Hattrick, we structure V&V from the ground up so it supports smoother submissions rather than becoming a last-minute scramble. Our team brings expertise in IEC 62304 software lifecycle processes, risk-based development approaches, and the specific documentation requirements that reviewers expect. If you’d like to learn more or discuss different V&V approaches don’t hesitate to reach out to us.