Any software used to enable a medical device for use on human patients in the United States is subject to FDA medical software compliance regulations.
Historically, building FDA compliant medical software was done using the waterfall method. The waterfall method was originally intended for developing hardware and was introduced around 1957. Absent any different programming or software development methodologies the waterfall method was adopted for developing software, including, but not limited to, FDA compliant medical software.
Documentation Needed to Apply for FDA Medical Software Compliance
The FDA gives required documentation for any software they will consider for compliance. These documents are listed and described in the FDA's "Guidance Development for the Content of Premarket Submissions for Software Contained in Medical Devices". The documents required include:
• Software Description
• Software Requirements Specification
• Architecture Design Chart
• Software Design Specification
• Traceability Analysis
• Verification and Validation
• Unresolved Anomalies
The Software Description
Let's talk about the first one here, the Software Description. This document must be, according to the FDA, a "summary overview of the features and software environment." It should be written in prose (ordinary language), and include specifics of the FDA compliant medical software, including the programming language, the hardware platform, the operating system it requires, and the use of any open source software in development.
The Software Description Using the Waterfall Method
The waterfall method of FDA compliant medical software development began with conceptualizing the project, then proceeded to initiate the software development process, analyze it, design it, construct it, and test it.
When the waterfall model of development was employed to build FDA compliant medical software, it usually began with developing a massive document outlining what the project is supposed to be (aka, what it "shall be"). Then, the document was more or less left alone until the completion of the development project, at which time programmers were charged with going back to complete the Software Description as required by the FDA. Since the waterfall model took a few months to a few years to produce a viable software product, a lot got forgotten between the drafting of the initial document and the time developers needed to complete the Software Description.
The Software Description Using the Agile Development Method
Enter the Agile method of FDA compliant medical software development. This method does not begin with the creation of a lengthy document, but it documents each step of the development phase "as it currently is," not "as it shall be". Upon completion of the software, you have all the notes and documentation you need to deliver the Software Description to the FDA.
To learn more about the Agile development and how it's used to develop FDA compliant medical software, download this free guide "5 Ways Medical Companies are Using Software & Apps."