Software verification

Testing is only one form of verification; reviews, inspections and traceability analysis count too. Good verification across the life cycle is what makes the final validation conclusion credible.

For the purposes of this guidance, software verification is confirmation by objective evidence that the output of a particular phase of development meets all the input requirements for that phase. Software verification involves evaluating the consistency, completeness, and correctness of the software and its supporting documentation, as it is being developed, and provides support for a subsequent conclusion that software is validated. Software testing is one of several verification activities intended to confirm that the software development output meets its input requirements. Other verification activities include source code evaluations (e.g., code inspections and walkthroughs), document inspections, design reviews, technical evaluations (e.g., software architecture, software detailed design, etc.) and traceability analyses (e.g., software requirements specification to software design specification (and vice versa), source code to software design specification (and vice versa), and test cases to source code and to software design specification). For example, the input and output of the design phase are known as Software Requirements Specification (SRS) and Software Design Specification (SDS), respectively. In this case, software verification would involve confirming by objective evidence (e.g., reviews, traceability analysis) that the software design as documented in the SDS (i.e., output) correctly and completely implements all the requirements of the SRS (i.e., input).

FDA guidance: Content of Premarket Submissions for Device Software Functions (June 2023), Section IV, Definitions