By Kathleen Straub, Ph.D., Chief Scientist for Human Factors International

How do customers decide which websites to trust? Consumer watchdog/research groups such as Consumer Web Watch (The internet arm of Consumer's Union) and the Pew Internet and American Life Project are keenly interested in answering this question. Both groups have recently reported large-scale surveys in which consumers reported that they rely on the following types of information:

1. Site owners/sponsors;
2. Reported information sources/citations;
3. Date of posting;
4. Clearly distinguished content, editorial content and advertising copy.

Here's what I say BUT watch what I do.

Both groups also report that, although consumers SAY that they use these factors to evaluate a site's authority and trustworthiness, when you watch them use the internet to find, learn and buy, they fail to systematically check things. Somewhat alarmingly, Pew reports that only about one quarter of health information seekers actually check the source and timeliness of the information they find.

So what characteristics are they really using? Fogg and colleagues at Stanford University have conducted two major studies exploring the characteristics of a website that influence perceived credibility. Participants were asked to explore/evaluate pairs of similar websites; rank the sites (within a given pair) as more or less credible than the other; and then report why they selected that particular ranking. In one study, Fogg's group observed consumers. In the second study, they explored if domain experts behave the same way

In the first study, a total of 2,864 consumers rated site pairs from one of 10 randomly assigned content categories: E-commerce, Entertainment, Finance, Health, News, Non-profit, Opinion/Review, Search Engines, Sports or Travel.

In the second study, a total of 15 experts ranked and commented on a random site pair in their domain of expertise.

What the studies found
Consumers who were not domain experts tended to use the same criteria to decide which sites were believable or not-independent of the type of site. The criteria used most often are (in order of frequency):

* Design look
* Information focus
* Information design
* Advertising
* Company motive
* Name and reputation
* Information bias
* Information accuracy
* Writing tone
* Information source

Domain experts took a somewhat different approach. For experts, the critical criteria were (in order of frequency):

* Name
* Information source
* Company motive
* Information focus
* Advertising
* Design look
* Information bias
* Information design
* Writing tone
* Information accuracy

Although these studies were conducted in the United States, similar findings have been found in other countries. In a study at the University of Heidelberg, consumers in a focus group confidently reported that they would look primarily to the information source to evaluate credibility of health information websites. However, in practice none of the participants explored the "About Us" sections of any of the sites that they visited. Further, participants could remember the name of the [Web site or] company or organization presenting task-critical information only about 20% of the time.

It seems that consumers use parameters of websites that they feel confident evaluating: look and information design. In short, attractive and easy-to-use websites are construed as being credible.

Why do people DO that?

It's not terribly surprising that attractive sites rate better. Social Psychologists (and marketers) have known for quite some time that attractive people are responded to more positively than unattractive people - they receive more help, more job offers, higher pay and shorter prison sentences [6,7,8 and 9]. In the absence of other criteria for evaluation (or even in their presence), perhaps the same holds true for Web sites?

The halo effect provides another explanation. A halo effect occurs when one positive characteristic of, in this case a website, influences the way that that object is viewed generally. For people, the positive characteristic is often attractiveness. We know that a halo of attractiveness broadly influences the perception of unrelated attributes:
* Attractive children are viewed as being less naughty than their less attractive peers for the same behaviors,
* Good-looking people are automatically assigned favorable traits such as kindness, honesty and talent.

Apparently, attractive websites are attributed with expertise and trustworthiness - the characteristics Fogg uses to define credibility - in the same way.

What does this mean?
If you are designing your company's website, this research has at least two important implications.

First, it's critical to know whom you are designing for: site characteristics that influence credibility for domain experts are very different from those which influence consumers.

Second, look and usability are intimately correlated with web credibility for both experts and general consumers. Although experts may employ additional parameters to evaluate your site, look and ease-of-use still rank high in their criteria for trustworthiness and expertise. For non-experts, look and ease of use are the most important source of usability for a website.

Not only are attractive, easy-to-use sites rated more efficient than frustrating or chaotic ones, examination of users' behavior clearly shows that these characteristics are critical to the overall credibility of the site.

Kathleen Straub, PhD, is the Chief Scientist Human Factors International a Usability Engineering Company with offices in among other places Baltimore, Maryland. HFI provides of usability integration mentoring, design consulting, usability testing and user-centered design training. kath@humanfactors.com 443.831.1351

References
[1] Fogg, B.J., Soohoo, C., Danielsen, D., Marable, L., Stanford, J., & Tauber, E. (2002). How Do People Evaluate a Web Site's Credibility? Results from a Large Study. Stanford Persuasive Technology Lab, Stanford University.

[2] Stanford, J., Tauber, E., Fogg, B.J., Marable, L. (2002). Expert vs. Online Consumers: A Comparative Credibility Study of Health and Finance Web Sites.

[3] Princeton Survey Research Associates (2002). A Matter of Trust: What Users Want From Web Sites. Results of a National Survey of Internet Users for Consumer WebWatch.

[4] Vital Decisions: How Internet users decide what information to trust when they or their loved ones are sick (March 2002). Fox, S and Rainie, L. Pew, Internet and American Life Project Report: Washington, DC.

[5] Eysenbach, G., & Köhler, C. (2002). How do consumers search for and appraise health information on the world wide web? Qualitative study using focus groups, usability tests, and in-depth interviews British Medical Journal, 324, 573-577.

[6] Benson, P.L., Karabenic, S. A. and Lerner, R. M. (1976). Pretty Pleases: The effects of physical attractiveness on race, sex and receiving help. Journal of Experimental Social Psychology, 12, 409-415.

[7] Mack, D. & Rainey, D. (1990). Female applicants' grooming and personnel selection. Journal of Social Behavior and Personality, 5, 399-407.

[8] Hammermesch, D. and Biddle, J. E. (1994). Beauty and the labor market. The American Economic Review, 84, 1174-1194.

[9] Stewart, J. E. (1980). Defendant's attractiveness as a factor in the outcome of trials. Journal of Applied Social Psychology, 10, 217-238.

[10] Dion. K. K. (1972). Physical Attractiveness and evaluation of children's transgressions. Journal of Personality and Social Psychology, 24, 207-213.

[11] Eagly, A.H., Ashmore, R. D., Makhijani, M. G. and Longo, L.C. (1991). What is beautiful is good, but…: A meta-analytic review of research of the physical attractiveness stereotype. Psychological Bulletin, 110, 109-128.