Bad news: surfing slowdown starts before you're 30

Stuart Corner
Tuesday, 01 April 2008 05:31

Business IT - Networking

Web usability 'guru' Jakob Nielsen has revealed the results of a study showing, he says, that "Between the ages of 25 and 60, people's ability to use websites declines by 0.8 percent per year - mostly because they spend more time per page, but also because of navigation difficulties."

He adds that "In other words, a 40-year-old user will take eight percent longer than a 30-year-old user to accomplish the same task. And a 50-year-old user will require an additional eight percent more time."

That’s' not too bad, but for those over 65, the news is really bad: "After 65 years of age or so, differences in user needs are so drastic that we require explicit steps to cater to them," he says. Nielsen claims that the results of the study, of 61 people are "statistically significant at the five percent level."

He also notes that "Individual differences swamp the tiny age-related difference in the 25- to 60-year-old group. Users are extraordinarily variable in their use of websites and intranets... Across a broad range of studies, our data shows that the slowest five percent of users are about five times as slow as the fastest five percent of users."

Nielsen says the steady decline is hardly surprising. "The human aging process starts around age 25 and causes erosion of cognitive resources, loss of visual acuity, degraded reaction times, and reduced dexterity. People need more time for the same mental operations; they have less memory capacity and take longer to process the same perceptual input. All of these elements of human performance impact the speed with which users can get something done on a website."

However there is another factor: the age at which people started using the Web. "Because the Web is relatively new, a 50-year-old might have started using it at age 40, whereas a 30-year-old might have started at age 20," Nielsen says. "In contrast, by 2050, a 50-year-old will have used the Web since age five, and thus benefit from 45 years of experience. A 30-year-old user in 2050 will have only 25 years' Web experience. This added experience might eventually allow older users to catch up and somewhat reduce the 0.8 percent gap."

For web site owners, Nielsen has two key pieces of advice: "When doing user testing, make sure to include test participants across the entire age range you're targeting [and] don't believe everything your 25-year old Web designers tell you about what's easy - especially if your target audience is 50-year-old corporate managers."