The purpose of the software validation is to provide objective evidence that software specifications conform to user needs and intended uses, and that the particular requirements implemented through software can be consistently fulfilled.
Depending on the type of software and its role within the medical device, the organization can apply different methods for validation.
Software validation is difficult because a developer cannot test forever, and it is hard to know how much evidence is enough. In large measure, software validation is a matter of developing a "level of confidence" that the device meets all requirements and user expectations for the software automated functions and features of the device. Measures such as defects found in specification document, est imates of defects remaining, testing coverage, and other techniques are all used to develop an acceptable level of confidence before shipping the product.