Clear information hierarchy
A clear information hierarchy is likely to help most readers (and for those readers that it doesn’t help, it will do no harm). The only caveat is that it can be quite difficult to create a clear information hierarchy. For example, if you were to just take an existing IFU design and create and apply design style rules to different information types, you could easily end up with a visual mess. The key to creating a clear information hierarchy is to consider design style rules alongside the IFU content, layout, navigation, ordering, form factor, paper folds and other key factors.
Streamlining the IFU
Shortening the IFU is a good aspiration, but in practice it is challenging. Some users will benefit from detail and rationale, and regulators will expect certain content to be included. However, do challenge every sentence and every word, especially those that are repetitive, negative, obvious or confusing. An IFU is not a script for controlling a machine, but a tool for optimising human behaviour.
Address ingrained mental models
Understanding the root cause of use issues is key to designing an effective IFU. In many cases, the root cause is an incorrect mental model. The best strategy may be to provide key information as early as possible in the user journey and/or explicitly call out differences between the device and similar devices. However, we know from experience that some preconceptions are too deep to overcome, no matter how well designed the information on the carton or the IFU. Only face-to-face training (or possibly digital animation-based instructions) can overcome what can only be described as a fundamental design flaw.
Test early, thoughtfully and frequently
Test your instructions for use with participants, but do so thoughtfully. A detailed IFU that performs well when directing participants to read it may give you false confidence. Such an IFU may perform well when used by the bee, but not when used by the seagull, sloth or puppy. Some stakeholders may be reluctant to change an IFU that performed well on a test (even if only tested with bees).
Answer fundamental IFU design questions early with focussed, little-and-often, testing. These tests can not only be enlightening, but they can also be cost-effective if study design elements are light-touch (e.g. protocol, IRB, participant group, location, environment, session length) – leave the process-shackles for late-stage confirmatory testing.
Closing thought
We need to accept that different people interact with instructions in different ways, and most will not read the entire IFU. When designing an IFU, we need to design for realistic IFU engagement by following a design process and design principles that caters for these differences. We must learn about the birds and the bees, as well as the sloths and the puppies.