You could almost think of this list of decisions as the story of your design. Along the way you will be constantly iterating: validating and verifying your decisions.

As you will have already seen in our Design Development Plan, we suggest having a plan for how you’ll your project from the outset.

Definitions

Validation: are we building the right thing?
Verification: does this thing we’ve built do all the things we said it should?

A DHF captures this story. It is the record of all the decisions you made along the way, and why. It is likely to be a group of documents, rather than just one (see below for tools you can use).

In the design of medical devices or software there are regulatory processes that mean you’ll often need to justify the design of a device or software. For instance, if you were creating a medical device and eventually wanted to distribute for use in the US, the device will need to be submitted to the Food and Drug Administration (FDA) for approval. As part of this submission you would need to provide a DHF. You may also need to provide this as part of the auditing process for other national and international regulations and standards.

Elements of a design history file

The key elements that make up your story:

• The starting point (called requirements in DHF)
  • Requirements
  • User Needs and Plan
• Your design (called design output in DHF)
  • Snapshots of your design
• Feedback and reviews (called design reviews and validation in DHF)
  • Research Insights
  • Meeting Minutes
• Arriving at a final design (called verification in DHF)
  • Verification Report

Other important elements might be if the requirements for the design changed for some reason, as this would mean the design would also need to change. It’s fine for requirements to change, but the change needs to be recorded.

In our experience, it’s much easier to integrate the recording of the story into our workflow than to try and construct it retrospectively. The risk is that the process of documenting while working takes a lot of time. We try and use lightweight digital tools that help us to record this history while maintaining our momentum and agility.

Tools for creating a design history

Any tools that help you record a chronology of events and link to other resources will be useful in recording your design history.

For instance, Git is a tool used widely for code management in software development. It can also be used to track changes in any set of files. You could also use any or a combination of these:

• A versioned wiki
• Google Docs
• Airtable