Source credibility is a key factor that can impact whether audiences believe a proposition, while trust is a key factor that can influence a person’s willingness to act on advice. In this blog post, I’ll discuss the historical use of source credibility in persuasion, present a humorous example of how the tobacco industry abused credibility appeals from 1920-1950, and finally, discuss why online credibility is important in the design of online outreach campaigns.
Over 2,000 years ago Aristotle discussed the role of source credibility as a key factor that can influence the likelihood that audiences accept arguments. He considered intellectual appeals based on reason to be more respectable than rhetorical appeals; however, he recognized that people are more likely to be swayed when good arguments are strengthened through emotional appeals, the speaker’s credibility, and a number of other contributors such as the presentation style and target audience disposition. Moving forward two millennia, in the 1950s, social scientists and communication researchers studying mass influence empirically rediscovered that source credibility was a key factors that influenced audiences’ likelihood of believing a speaker, and consequently, it was a quality that could be employed in the design of mass communication campaigns. For example, companies employing high credibility celebrities could better sell their products, while celebrity spokespersons could better solicit charity donations.
Although there are different definitions of credibility, it is generally considered to mean believability. It is composed of two dimensions: perceived expertise and trustworthiness. For celebrity endorsers, visual appeal is considered a dimension of credibility while in online environments, visual design could be a key dimension (or strong correlate) of online credibility. Research suggests that people rely on credibility judgements to determine what they believe when they are disinterested or only know a little about an issue. For example, if a friend I trust expresses an opinion within his area of expertise, and I have little background in it, then I just may adopt his viewpoint. However, if I know a lot about the topic, then I’m more likely to be swayed by the strengths of his arguments, rather then the strengths of my convictions that he knows what he’s talking about.
Perhaps the best, worst and funniest examples of credibility appeals come from tobacco industry advertising between 1920 and 1950. During this time, tobacco companies compensated for their credibility deficit by borrowing the medical profession’s credibility. Although morally outrageous; these ads proved an easy to understand example of credibility appeals, plus they’re quite funny.
Believe it or not, during this time numerous tobacco companies launched ad campaigns that co-opted medical authorities into endorsing smoking. Based on an American nation-wide survey, Camel produced an ad campaign claiming that “More doctors smoke Camels than any other cigarette”. Although this statement may have been statistically true, the portrayal of medical figures–who are responsible for protecting public health–implied that smoking was probably not bad for you, and may even be good for your health.
Through visual and written arguments, the ad above makes a number of appeals directly to audiences’ trust and credibility judgements. Visually, the background is built from a collage of images portraying the truth seeking and independent nationwide survey that proves their claim, that more doctors smoke Camels. Secondly, the primary image shows a healthy looking older doctor who’s enjoying a puff of smoke while the body copy informs readers that he is just one of many doctors across the country who enjoy smoking, implying that the medical community endorses smoking.
Though I’ve not studies the history of the tobacco debate during this time period, I understand there were concerns about smoking and health. Anecdotally, my grandfather started smoking while serving as a solder during WW II and just after 1945, his doctor threatened that if he didn’t quit, the cigarettes would kill him. Fortunately, my grandfather didn’t heed the advice of the tobacco industry ads in circulation at the time, but rather, he followed the advice of his doctor and quit cold turkey. Although the medical evidence against smoking was not conclusive at this time, there was opposition to smoking and it’s hard to imagine that these ad campaigns were anything other than a mens rea attempt to mislead the public.
By co-opting the authority responsible for defending public health, this ad campaign borrowed credibility from the medical community to harm, rather than protect the public’s interests. This was just one of many credibility-based ad campaigns at the time. Other co-opted sources included smoking nurses, scientists, dentists, celebrities, priests and even Santa Claus. If this deceptive advertising has placed you in a foul mood, you may want to boost your spirits by having a good laugh. Just visit Stanford University’s archive of tobacco advertising.
Although many social marketing campaigns are based on sound research and engage high credibility stakeholders, such as state health departments or reputable non-profit organizations, online campaigns are increasingly operating in a low-trust and high-competition environment. In cyberspace, tobacco advertising runs unchecked, pro anorexia websites can outrank health campaign websites, and online crime is so successful, that it’s pulling in billions. For these reasons, the importance of credibility and trust are critical to the success of online communication strategies.
There is a large body of research that suggests people misattribute human-like qualities to websites, and interact with technology as social actors. Consequently, when people interact with online campaigns (through websites, email, social networking groups, etc…), their superficial judgements of the media they encounter can impact their credibility judgements more than actual knowledge of the organizations running the campaigns. This is important because growing literature, and my own empirical research, suggests that website credibility can be critical to soliciting target audience trust and participation. Just as consumers who want to buy a product online are less likely to enter their credit card number into a bogus looking ecommerce website, potential supporters of campaigns are less likely to support campaigns that does not appear credible, by their particular measure of what constitutes credibility.
A few practical implications of this principle are that online audiences may conceptualize campaign websites (in part or whole) as the credible source, consequently, it may be useful to conceptualize websites in human terms and model interactions between users on human-like relationships. For example, the Barack Obama campaign websites provide excellent examples of engaging users in direct, one-with-one personal relationships where Barack speaks directly to you. Second, as credibility is regarded as a perceived quality, target audiences should be the ultimate judges of what constitutes a credible and trustable online campaign. Third, when designing interventions, online content should, where appropriate, demonstrate the campaign’s expertise and trustworthiness through written and appealing visual language. Finally, to outperform online competition and competing behaviours, it is possible to stand out by having a more credible and trustable online campaign than the competitors. Conversely, the same factors used to design credible appearing campaigns can be leveraged to undermine the credibility of competitors’ campaigns. As an example, the Truth anti-smoking campaign was more like a grass-roots advocacy campaign that attacked the tobacco industry’s credibility through charges of misleading the public. Likewise, Joe Chemo ads use wit and visual rhetoric to challenge the tobacco industry’s pro-smoking portrayals by demonstrating the scary cause-effect relationships between smoking and ill health.
For more information and practical campaign advice, my work on website credibility and trust appear in the following publications and presentations:
Publications
- CUGELMAN, B., THELWALL, M. & DAWES, P. (2009, in press) The dimensions of website credibility and their relation to active trust and behavioural impact. Communications of the Association for Information Systems.
- CUGELMAN, B., THELWALL, M. & DAWES, P. (2008) Website Credibility, Active Trust and Behavioural Intent. PERSUASIVE 2008, LNCS 5033. Berlin, Heidelberg, Springer-Verlag.
Presentations