6 Considerations for Designing an Effective IFU

Have you ever tried to use a product or put together a piece of furniture by looking at the instructions and struggled to follow the provided steps? We can all probably think of at least one set of instructions that was either all text or only figures. Without the complete framework, we are left with a considerable amount of guesswork. Imagine a world where all of the instructions were made by IKEA (in other words, ALL diagrams, NO written instructions). How much confidence would you have in your ability to follow that style of instruction for your next medical procedure? Now consider, with “IKEA style” instructions, are you positioning your combination product or medical device to provide the best user experience.

Design of effective and logical Instructions for Use (IFU), sometimes called a user guide, is critical for ensuring a medical device user’s safety and comprehension, as IFUs are used to inform the novice user how to use the device.

Designing an effective IFU begins with the completion of a task analysis and the integration of the steps outlined by risk management. Risk management procedures and human factors evaluations provide the framework for identifying and mitigating use errors stemming from poor IFU design. The integration of risk management and usability is key! 

While that is key to getting your content right, it is important to note that an effective IFU is a harmonious combination of content and organization. A detailed, content filled IFU with no organizational structure is just as ineffective as a structured IFU that is lacking quality content.

IFU comprehension is an important area that is included in a Human Factors/Usability Engineering (HF/UE) evaluation and in summative studies for product validation. Therefore, it is important that as much care is taken to design an effective IFU as is taken to design an effective (and safe) product. In the combination product space, pharmaceutical companies usually purchase an already designed drug delivery device from an external vendor. In these cases, changes to the device may not be possible, and reliance on the IFU to improve the user experience is further increased!

Unfortunately, not all instructions are developed with the same level of care and attention to detail. Sometimes IFUs fall short because creators err on the side of simplicity versus clarity. Sometimes it is because there is a heavy emphasis on the content of the IFU, but almost no thought has been placed on the organization of the IFU. To assist with user comprehension, it is important to remain consistent and mindful of how information is being presented and look at your IFU from many angles.

Here are six design considerations that we have recently come across while evaluating past clients’ IFUs.

These considerations represent a general overview of different areas, but not an exhaustive list, within IFU design where mistakes were made that decreased the comprehension and readability of IFUs we have been asked to improve.

It is important to consider both the broad and the narrow categories of intended users. Thinking broadly, the organizational flow and structure of an IFU should allow for both novice and experienced users to quickly find and understand information. Even though increased exposure to the device interface decreases reliance on the IFU, more seasoned users may still have to refer to the manual if they forget how to complete a task or find a specific option. Remember to also be wary about the amount of technical language that is used in the instructions for how to interact with the device – a novice user may not be familiar with all of the advanced terms.

Thinking narrowly, there are many segments of your intended market that may require dedicated consideration as you design your IFU, from age to physical ability to languages spoken. For example, every country represents the potential for new customers and the presentation of unique challenges. The success of the product is influenced by how well the product matches and informs the intended user population within that country. It is important to consider each country’s primary language and socially accepted symbols when developing the IFU. Subtle language differences in spelling (e.g., US English compared to UK English or Canadian English) may cause confusion, albeit temporary, among users. Conducting reviews of IFUs has allowed our team to identify issues around intended user population’s language or clinical acronyms. Subtle differences in wording can lead participants to become puzzled while reading the instructions. Participants in past evaluations have paused and asked for clarification when reading text that has been written using UK English instead of US English. Users have also dedicated extra time to find definitions for unfamiliar acronyms. Something as small as unrecognizable acronym can potentially delay critical care.

One flaw that we have seen in IFUs is a lack of organization for how the information is presented. This lack of organization can be seen across the whole IFU or it can be isolated in specific sections. IFU comprehension can be augmented through organizing instructions with an effective combination of visuals and text. A structure that includes both, clearly paired together, allows your IFU to speak to users that grasp visual cues and users that require text instructions, and also provides deeper clarification of directions for each.

A task order of operation can also create confusion if it does not follow a logical progression that matches with the actions required by the device’s interface. Many times, steps are skipped or not defined with enough detail to provide the user with the necessary information required to complete their goal. Even though it would be recommended and may be considered best practice, the average user is not going to be reading through the IFU from the front page to the back in one sitting. So, if an IFU lacks a logical organizational flow, novice users can struggle with finding pertinent information at the right stage of use. A delay in finding pertinent device information may not have any implications when the search is for personal edification. However, if attempted during an emergency use, it could lead to patient harm or death. This can be better avoided if the IFU is designed with a logical progression of tasks that are identified by completing a task analysis. A task analysis will identify a task order of operations which can be used to develop the structure for how to discuss each step in the IFU.

Word processors such as Microsoft Word have three main font styles to emphasize text: (1) Bold, (2) Italics, and (3) Underline. Each of these font styles can help important text stand out in the IFU. But it is not just the use of font styles that is important. It is also the consistency in how these styles are applied in the text (what type of text is presented in each emphasized font text). Typographical emphasis should be used methodically and with moderation to allow for the best result. Too much font in bold will lead to all of the text looking the same or the user will consider all of the text to be important. Conversely, too little bold font or inappropriate text in bold can lead the user to miss an important step.

The two keys to the use of color are (1) the consistency of color-coding and (2) the color contrast ratios. Color can be useful when attempting to differentiate different pieces of product or text.  Color-coding can increase the usability of the product if applied appropriately, however, as with typographical emphasis, if the color-coding is applied incorrectly this could result in user error. The user error may be a result of the inaccurate color-coding in the IFU for the device itself, the device’s interface (i.e., displayed information such as digitally presented on a screen), or accessories associated with the device. Extra care should be taken to ensure that the color on the physical product or display matches with the image that is provided in the IFU.

When dealing with colors, it is also important to remember to keep in mind appropriate color contrast ratios. If there is not enough contrast between colors, it can become difficult to read the text. If the IFU is printed in greyscale or black and white, caution should be taken to ensure that the colors chosen will be visible if printed in those schemes.

Common image flaws to remember when developing an IFU are: (1) small or low-quality images, (2) inaccurate images, and (3) inappropriate labeling of an image.

Images provide the user with a visual representation of what they are reading in the text. If the image presented does not clearly match what the user would actually see during that step, it is possible that the user would become confused or make an error. The issues caused by small, inaccurate, confusing, or low-quality images is compounded if the images are explicitly referred to in the IFU text.

Another flaw that we have seen is not labeling the described parts of the device in the image. Providing labels for the images helps the user to match focal points of the text in the image. Not only should the labels help identify the important components presented in the image, the image itself must be clear enough to easily depict those particular components. Any diagrams should be of an appropriate size and detail. Without this, the user may misconstrue the information and not be able to correctly follow the instructions.

Due to the complexity of their work environments, the IFU may not be how many clinicians learn how use the product. Some more impatient or time-pressed users also may not find an IFU to be the best method of learning for themselves. While developing the IFU, another recommendation is that supplemental material – such as a quick reference guide – be considered. This allows the clinician and other users to easily access the most important information. Obviously not all devices need a quick reference guide, but it is beneficial to have them for complicated devices that may have more functionality and options compared to a simple device such as an autoinjector.

As you can see, designing an IFU is a complex task with many facets to consider. For the safety and user experience of patients, it is always best to allocate the resources and attention to get your IFU right.

The Suttons Creek, Inc. Human Factors team has the expertise to help review your current IFU and will support you with additional reviews and feedback for future iterations. Feel free to call for a complimentary consultation.

Matthew Nare, Consultant – Matthew Nare is a junior consultant on the human factors team for Suttons Creek, Inc. His previous work as a physical therapy aide provided an opportunity to gain clinical experience in inpatient and outpatient rehabilitative care settings. He came to Suttons Creek Inc. following an internship completing clinical observational research with MedStar Health’s National Center for Human Factors in Healthcare. Additionally, he spent over a year completing accessibility evaluations at Cal State Long Beach’s Center of Usability in Design and Accessibility. This combination of work experience and his educational background provides him with a unique perspective on how the medical devices and their users function.

LinkedIn: Matthew Nare