How does Web Credibility Relate to Web Design?

Two years ago the Stanford Persuasive Technology Lab produced a study showing that visuals are very important to some users when judging the credibility of web sites. Since then, some designers have used that study as a way to back up the importance of focusing on “visuals” while designing. I’m not so sure…

Recently web credibility has gained interest in web design circles, most notably Digital-Web magazine. There, Dirk Knemeyer, in his article The End of Usability Culture, cites the results from a large study done by the Stanford Persuasive Technology Lab called How Do People Evaluate a Web Site’s Credibility? He used this study as support for his argument that visual design is very important to people using the web, and therefore is a very important aspect of web design.

Knemeyer sums up the study as follows: (the study) “reveals that consumers place more emphasis on ‘design look’ and ‘information design’ than on ‘content evaluation’. … Visual design is every bit as important as usability, findability, and accessibility.”

Knemeyer isn’t the only one citing this study with reference to design. George Olsen cited it when reviewing Jesse James Garrett’s book The Elements of User Experience on Boxes and Arrows. Olsen used it as support for the “surface” level of James’ description of web sites. He put it like this: “And yes, looks do count. A recent study on website credibility found 46.1 percent of those surveyed mentioned the site’s appearance in assessing it—
far more than any other factor. (The next closest factor, information design/structure, was mentioned only 28.5 percent of the time.)”

Credibility Study as Design Suggestion

Both of these examples use the study in an interesting way: they use it to back up claims that visuals of a web site are important, and our design efforts should be adjusted accordingly. Knemeyer’s claim is that the usability culture that has pervaded the web industry over the last few years should turn their attention back to design (of the visual kind). Olsen claims that visuals are an important shorthand evaluation on some types of sites, especially when other parts of the site are difficult to evaluate, an astute observation, in my opinion.

Don’t get me wrong: I think visuals are hugely important, and a major influence in how people view the world, make sense of it, make judgments about it, and make decisions about it. But I’m not yet willing to make any claims about how this seeming importance of visuals should influence our web design practices, yet. (and only with claims that visuals are important—and not specific design practice changes—these two authors might not either)

Do We Know What Credibility Is?

But what exactly is web credibility? When the test participants in this study were asked to judge the credibility of the web sites, what did it mean to them? Was it the same for every person, or did people have different ideas about what credibility is? Is it possible to measure what instills trust in people? Can we really understand what powers our beliefs? And, in great irony, should we believe those people when they tell us what powers their beliefs?

The biggest assumption that the study makes, in my view, is that credibility is something that can be judged by simply asking people after they quickly view a web site. In most cases trivial experience elicits trivial data. As I wrote in response to Dirk’s article: “it certainly seems to make sense that, given nothing but visual design upon which to make a judgment of credibility, that visual design would win out!”. In other words, test participants didn’t interact with the web sites in any meaningful way other than to look at them, and because of that they simply noticed the visuals more than any deeper content concerns. In everyday use this would probably be the other way around: users would be much more interested in content after they’ve experienced the visuals.

This is not to say that I disagree with these results. I don’t. But I do wonder how useful they are to web designers given that the population of test participants was familiar with some sites and not familiar with others and that those specifics were not reported. That, to me, is a crucial factor of an assessment of any site.

Test Participants Hinted that Familiarity was Important

And users may have even hinted as much. In the e-commerce portion of the study, “name recognition and reputation” was the number one issue that users noticed when judging credibility. But what we don’t know is whether or not the test participant was familiar with those sites upon which they made these judgments. I wonder if these comments were made on sites with a large customer base and a lack of “compelling” visuals: sites like Amazon and eBay, or if they were made on those sites where users had little else to go on except for a first impression (perhaps they hadn’t used the site or never even heard of it). After all, we tend to judge things that we don’t know about by looks alone, as Olsen hinted at. Without knowing which comments were made on which sites, and what the test participant’s previous experience was on that site, I find it hard to understand what these results mean for designers.

Judgments Aren’t Built in a Day

As I’ve written before, we tend to judge things quickly for the sake of efficiency. The reason why we do this is that it often works. Our eyes do great work in helping us through our day.

However, human experience also shows us that judgments don’t always depend upon quick reactions to things, as this study suggests. For example, we don’t simply decide whom to vote for on the day of the election (the consistency of state voting attests to that). We also don’t decide to buy books from just any old bookseller each time we need to purchase a book: we look to our past experiences to help us out. We also don’t go to the web, find the greatest looking bank web site, and start using it without considering anything else. These things should temper any desire to hold up (any) study and proclaim that the results show something definite about the practices or proposed practices of web design.

As this study suggests, credibility is not easily measured. It is made up of factors that are difficult to understand and hard to quantify. In the quest to figure out just how much visuals affect credibility (and thus design), I think this study is highly interesting, but only just a start.

Published: November 16th, 2004

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