Product Designers: Could We Accommodate More Human Variability in Design?

Posted by Mike, on April 29, 2016

As designers, we are often charged with developing products that fit with the human body, such as wearable electronic devices, handheld tools, and larger-scale equipment like surgical tables and CT scanners.

This would be an easy task if all humans were built alike, or if each product only had one unique user, but that’s not likely the case. In reality, there are many types of people who will be using the product you are designing.

This is particularly true of products developed for service industries, like healthcare, where you not only have to design to accommodate the patient, but also the surgeons, nurses, anesthesiologists and others who will be interacting with the device in different ways for different needs.

All of these considerations create quite the complex design equation, which can leave you battling with extremes, and, we hope, pondering a big question: how do I design for the largest group of users possible?

How Designers Commonly Address Human Factors in Design (And Where This Approach Falls Short)

It can be very difficult to make a product that fits every possible user type. Instead of trying to accommodate everyone, product developers commonly decide upon some portion of the population to design for, usually the most common portion, like the 5th percentile female to 95th percentile male, for example.

While this approach makes a lot of sense and is very practical, it can also cause designers to limit their creativity into set parameters, and removes potential product users from consideration before better possibilities are even fully explored.

Before locking and setting design requirements in stone, designers should first ask the following questions of their initial product concepts:

  • Are we accommodating every type of person that we possibly can? Or are there innovative ways to accommodate more people than this initial concept allows?
  • What could the concept look like if we accommodated demographic A, B, and C too? Is it feasible?
  • What would it cost to manufacture this product before and after we accommodated demographic A, B and C?
  • If we do not include demographic A, B, or C into the concept right now, how will that impact the usefulness of the product in the target market? In other markets?

When we stop and ask ourselves these questions, what can happen? Read on for a quick case study example.

Ergonomic Design Improvement: 

SmartShape Enhances Medical Stretcher Chair

When someone goes to a hospital it is often not by choice to begin with, and they almost certainly have no choice in the type of equipment that will be used on them. (And nowhere is the importance of good ergonomic design more critical than in healthcare.)

Increased accessibility and range of use could be the difference between a patient getting the assistance he or she desperately needs, or being left in pain.

Let’s dive into a specific example.

Below is a medical stretcher chair. The patient sits in the chair, which converts into a surgical table, when they arrive to the hospital waiting room with immediate surgical needs. 

Medical Stretcher Chair

The patient checks in, prepares, takes part in needed surgical procedures, and is wheeled to recovery, all without leaving this same chair.

In the past, this manufacturer set out to accommodate the US 5th percentile female to 95th percentile male. The result ended up to be a compromise, designed to fit the average height users, but poorly accommodated shorter and taller people.

As you can see in the image below, this woman can’t get into the chair without standing on a stack of cardboard. 


And this tall guy feels he is sliding off the chair because the seat depth is not deep enough.


When this company asked our team at SmartShape to help optimize the ergonomics, we wanted to make sure we kept everyone in mind, including smaller and taller people like both of these individuals.

Rather than limiting ourselves at the outset by deciding to design for the 5th to 95th percentile, we pushed against the existing limitations and asked ourselves, "What is the lowest we can make this chair go, and still have room for the mechanical structure? How can we achieve more height and seat depth?"

The result was a new concept, able to adjust in size based on individual user metrics, reaching lower than existing products (well below the 1st percentile US female), and automatically shifting in height and seat depth for taller people. Not only does this design include more people at the extremes, but it actually fits them well. 


Now, when a new patient arrives, the healthcare provider simply has to ask the patient or a family member for the patient’s height and, with the help of an intuitive user interface, the chair automatically adjusts to be exactly what the patient needs to sit and receive care safely and comfortably. A win for all involved.



Could Your Design Concepts Improve to Include More User Types?

Think on a few of your latest and greatest products. Are they designed to fit the wide range of human variability amongst users in your market? Perhaps the 5th to the 95th percentile? Might it have been feasible to accommodate more people at the extremes?

And, are we doing our best to really accommodate people at the extremes, or are we instead compromising, designing for the average, and poorly accommodating people at the extremes as a result? (The same as making a size 10 shoe to fit people sizes 5 to 15?)

At SmartShape, we think these are critical questions to consider.

After all, taking the extra effort to explore the possibilities beyond a certain set of best practice ergonomic metrics, and taking the responsibility to try as hard as we can to find ways to make products as accessible as they can be, could be what puts a live-saving tool in just the right size set of hands.

What steps do you take to ensure ergonomic success in product design? How do your designs reach more of the markets your client or company serves? Share in the comment section below.