Posted in Website Usability Testing	October 7, 2005

While humans are humans, age is a major consideration in designing usable websites that will allow the targeted users to have an efficient and fulfilling user experience.

Executive Summary

• Website usability testing reveals stark differences in the way seniors and teens use the Web to complete everyday tasks
• While seniors take longer, they can reach their goals 85 percent of the time
• It's critical to adhere to best practice website usability guidelines for both groups

I love website usability testing. There is no activity in my life that is more sobering and satisfying. My life as a website information architect working in 2005 is akin to that of a prehistoric hunter stalking the wooly mammoth. It's not pretty, but we get the job done.

Most of the websites I've designed and tested over the past 10 years have been created to serve users with an average age of about 45. Last weekend, I spent the better part of the day doing website usability testing with a group of teenage college students. A few weeks earlier, I spent two days with a group of seniors whose average age was 62. These groups—teens and seniors—represent the extremes of the current human-computer-interface (HCI) continuum for website usability testing.

After the second set of website usability labs, I decided to do a little analysis of the differences between the two groups that could be represented quantitatively:

Mequoda Usability Labs - Age Impact Summary
Key Metrics	Hub 1	Hub 2
Average Age	19	62
Number of Tasks	10	5
Average Time in Minutes	32	78
Success Rate	100%	85%

While the average five-task website usability lab takes about an hour for each 30- to 50-year-old participant, our seniors took an average of 78 minutes, with one 65-year-old user taking 108 minutes to complete five website usability tasks. The senior group's overall website usability task completion rate was 85 percent—a little below average for Mequoda websites, which are fundamentally simple to operate by design. As noted before, I believe we must keep website functionality simple today based on our industry's near-Neanderthal technological capability to design truly friendly websites that offer robust functionality and are still intuitive and easy to use (remember my earlier analogy to stone knives and bear skins).

While the websites for both groups were Mequoda Internet Hubs with similar architecture and functionality, the website for the college students offered more than double the topics plus advanced functionality not available in the website for the older group. Due to the complexity of the college website and our anticipation that the college students would complete website usability tasks more quickly, we boldly doubled the number of website usability tasks to be completed by the students.

To our amazement, each college student completed all 10 website usability tasks in an average of 32 minutes with the slowest student, relatively speaking, taking 35 minutes. Miller Time came early last Saturday. I've never before run a website usability lab series with a 100 percent task completion rate for every participant in any amount of time!

Lessons: I have always assumed, until now, that the human side of HCI was more or less a constant based on the limits of human physiology, and that improvements in websites usability were dependent on technological progress. I was wrong. Every one of our randomly selected students performed most of the website usability tasks with the Borg-like efficiency of a person totally familiar and comfortable with the user interface of a website they had never seen before the website usability testing began on Saturday morning. The next generation of the human race is evolving to be excellent Internet users.

Before you get too excited about the state of human evolution, let me make two points:

1. Mequoda websites are best practice websites that tightly adhere to website usability standards set forth in documents like the Mequoda Website Design Scorecard. They leverage the familiar mental models that these young adults have come to see as normal. To them, blue, underlined text has a meaning every bit as clear as a red, octagonal street sign with the letters "STOP."

2. Unless you don't care if your website is usable for humans over the age of 30, you'll need to keep your website simple, streamlined and task light for awhile to come. Older folks are also slowly learning the symbology of website design, but their understanding is not fluid. For them, website symbology and architecture is a learned language that must be translated on-the-fly in their brain the way a late learner of French still thinks in English to process information.

Age makes a huge difference is website usability, and every segment of the population with computer access is learning to use the Internet as a second language. For your websites to succeed, it should use and promote the website usability standards that are quickly becoming as common as traffic signs, remote controls and cell phones. As with any language, standard meanings are critical for effective communications.

Recommended Resources

• Teenagers on the Web—Nielsen Norman Group, "60 Usability Guidelines for Creating Compelling Websites for Teens"
• Web Usability for Senior Citizens—Nielsen Norman Group, "46 Design Guidelines Based on Usability Studies with People Age 65 and Older"
• Making Your Web Site Senior Friendly—National Institutes of Health
• Web Usability and Age—Fidelity Investments & Bentley College, "How Design Changes Can Improve Performance"

Note: The details of the case have been modified to protect the identity of the publisher and program. If you've got a case study you'd like to share, drop me an email. Your privacy is my top concern.—Don Nicholas