Aidan Petrie, Chief Innovation Officer and Co-Founder, Ximedica

Designing for an Aging Clinical Population

By Aidan Petrie
Aidan Petrie, Chief Innovation Officer and Co-Founder, Ximedica

Aging has important implications on design, the most significant of which puts emphasis on graphic and product user interfaces.

The Boomer population is coming of age in rapid succession. Within this 72 million-strong demographic group is a sizable clinician, nurse and caregiver populace that both may desire to remain part of the workforce, and will be advantageous to retain. 
The AMA’s Physician Characteristics and Distribution in the US 2011 reports 63 percent of all physicians are aged 45 years and older. From this group, 20.7 percent are 65 or older. Further research proves that Registered Nurses aged 50 years and over are also on the rise.
Through our own research efforts studying active clinicians in their work environments and healthcare product development activities, we have seen innumerable areas where aging has important implications on design, the most significant of which puts emphasis on graphic and product user interfaces.  
Graphic user interfaces
Graphic user interfaces or GUIs are among the worst design offenders in making life more difficult for the aging population. Contrast and font size are the most critical elements of readability but users also benefit from a simple relevant interface that controls or displays the states of use. Developers often use terminology that is unique to their product compromising cognition or clutter screens with too much and un-prioritized information.
Design elements to consider when designing a GUI for an aged user are:
  • Higher contrast appropriate of displays and inputs, particularly in low light settings;
  • Larger, more readable fonts;
  • Familiar pictographs and clear text messaging aids cognition;
  • Intuitive navigation through the operation of a device;
  • Clear feedback when selected settings have been implemented (such as bolding of function label); and
  • Prioritizing information on screens based on criticality.
Product user interface
When we reference a product user interface or PUI, we consider all of the interfaces between the form and the human. These could be buttons, knobs, foot controls, handles, levers and more, anything that needs to be touched in order to operate a device. Weight, size, and form have to consider what the intent of a control is with respect to who is operating it, where it is being used and for what purpose it is used.
Understanding that age effects strength, dexterity and vision means additional consideration needs to be given to the weight of equipment and the size of operating controls on a device that might pose challenges for this user group.  
Often time improvements are simple and obvious, such as changing the clamp color on an IV tubing set to bright orange so that it is easily visible to a nurse in a hurry to start an infusion on a patient, or making sure there are audible clicks when the tubing is fully engaged in the device. 
Another example would be lengthening a trigger on a device enough to fully accommodate two fingers rather than one for added torque and a reduction in user fatigue. This would also work to alleviate any discomfort incurred from poor fit such as force on pressure points.  
Concern has also been raised on instruments where the requirements of strength and dexterity coupled with long or repetitive procedures result in various stress issues such a carpel tunnel. In fact, a survey developed at the University of Maryland, School of Medicine, found that 87 percent of laparoscopic surgeons have experienced physical symptoms or discomfort. The reason for this rise in incidence is due to the constraints these surgeons face that are not part of an open surgery. During a procedure, movement while operating is extremely limited as the surgeon maneuvers long and oftentimes heavy instruments through tiny sites.  
Design elements to consider when designing a PUI for an aged user are:
  • Tactile feedback;
  • Controls that can be distinguished by touch;
  • Clear labeling on all controls , using large print;
  • Anthropometrics and biomechanics; and
  • Forces to activate controls. 
As medical device manufacturers meet the challenge of product development for an aging healthcare provider, so too will they meet the increased scrutiny the Food & Drug Administration (FDA) has placed on device usability. The release of their latest draft guidance on human factors engineering and usability evaluation in June 2011 clearly calls for a demonstrated knowledge of human factors throughout the entire design, development process.

About The Author

Aidan Petrie, Chief Innovation Officer and Co-Founder, Ximedica