Why we need better UI in patient-used medical devices | PDD

Why we need better UI in patient-used medical devices

By PDD

on August 20 2015

Economic driver for home healthcare

It’s no secret that our healthcare bill is increasing. Worldwide, healthcare spending is at a record high, and an expanding and aging population means this shows no sign of slowing down any time soon.

One way of coping with this demand is to get patients who need specialist equipment to treat themselves at home. Healthcare professionals (HCPs) have been prescribing patients small medical devices such as blood pressure monitors and blood glucose monitors for years; however now we are starting to see larger more complex devices such as nebulisers, infusion pumps and even dialysis machines given to patients for self-treatment.

This trend has clear benefits: The more patients can care for themselves, the less time they need to spend in a hospital (or other healthcare facility), thus freeing up precious capacity in the healthcare system (both HCP time and hospital beds).


A patient carries out a dialysis procedure in his own home. Image credit: redding.com.

Risk of use errors

Unfortunately, as more patients start using more complex devices at home, the chance of use errors increases, and the ensuing results can be deadly. An error whilst using Facebook could result in you uploading the wrong photo, an error whilst using an infusion pump could result in a lethal overdose. Understandably preventing such use errors is taken very seriously. The Food and Drug Administration (FDA) in the US, for example, requires usability tests for all healthcare devices prior to granting them regulatory approval and won’t approve any device that could cause a fatal use error.

Key role of the user interface

User Interfaces (UI) have a key role to play in reducing the risk of use errors in a patient-used device, especially now that more patients use increasingly complex equipment. In fact, the benefits of a good UI go beyond reducing errors. People generally like using products that feel easy to use and creating a device that patients feel good about has the potential to improve their well-being, increase treatment adherence and better overall health.

Unfortunately, UIs of patient-used devices available today are often lacking. This is due to a range of factors, including a lack of competition as well as the fact that a device is often selected by the HCP, not the patient who is the ultimate user. To complicate matters more, the payer for the device is typically another party such as a private insurance company or national healthcare provider (e.g. NHS). As a result, parameters such as functionality, reliability and value are still often seen as more important.

However change is on the horizon, improving interfaces doesn’t have to be hard. Often following simple design principles can improve the user experience, a few examples of these include:

Speak in a language users will understand
Patients generally won’t have the same level of understanding as medical professionals. All text should be in plain language and should explain terms and phrases that patients may not be familiar with. This is especially important if something goes wrong. If an error occurs, the device should display what happened clearly and suggest a solution for the user.


Accu-Chek® Aviva Expert glucose monitor error message. The device states an error has occurred, what caused the error and what the patient should do next. Image credit: healthline.

Reduce reliance on instructions
Of course, patients should always be familiar with instructions before using any medical device. Unfortunately, though, instructions can get damaged or lost, and often patients do not think they need to read them. To overcome this problem, always design interfaces that provide guidance and help for any first time users.


Fresenius Medical Care Liberty® Cycler continuous cycling peritoneal dialysis machine. The screen has a clear step by step guide of how to set up the device. Image credit: Spare part transformations.

Reduce cognitive load
Every extra piece of information a patient has to remember when using the device will increase the chance of a use error. Make vital information visible at all times and try to cut down on the amount of information a user has to enter. If a patient is likely to use only one dosage setting, keep it in an internal memory instead of making them enter it every time they need to use it.


Braun Vista® infusion pump keeps an internal memory of the last settings users entered removing the need to re-enter them every time. Image credit: dotmed.com.

Reduce capacity for errors
Even the most experienced patients are still capable of making the occasional error.  Anticipate where errors are likely to occur and design the device in a way that prevents this happening. If a patient enters a value that is far higher than what they usually enter, insert a warning before they proceed.  Controls placement plays a large role as well; keep important controls such as “activate” or “power” in locations where they will not be pressed by accident.


The easypod™ auto injector separates the main interface controls on the front of the device from the injection activation button on the top of the device. Separating the controls means patients are less likely to trigger an injection accidently or until they are absolutely ready. Image credit: Merck Serono.

Designing a winning patient experience

A final word… User interfaces should always be tackled in terms of the broader patient experience rather than designed in isolation. Even the best UI in the world will not help if a medical device has poor physical ergonomics or is too impractical for a patient with limited mobility to use. Everything from how a patient communicates with their doctor to how they receive their medication should be taken into account when designing a device, and using a Human-Centred Design process can help you achieve this.

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