How to convince people to wash their hands during flu season

Suppose there were signs in a restaurant bathroom telling customers that they must wash their hands. Would customers obey them? It really depends on the tone of the sign and whether the message praises or scolds, says a forthcoming study in the Journal of Marketing Research. According to the study, to persuade customers to behave in a certain way, businesses should praise with an assertive tone and scold with a non-assertive tone.

"In order to influence consumer behavior, marketers will either praise consumers or scold them," write the authors of the study, Amir Grinstein (Ben-Gurion University) and Ann Kronrod (Michigan State University). "But what is just as important is how those messages are delivered. In other words, tone is important."

The study is one of the first to examine the role of tone—in this case, an assertive tone—in those kinds of communications. To determine the influence of assertiveness, the authors conducted two field experiments. In one experiment, they encouraged hand hygiene; in the other, financial planning. In both cases, they tried out four messages: praising with an assertive tone; praising with a non-assertive tone; scolding with an assertive tone; and scolding with a non-assertive tone. They then tested their findings in a controlled laboratory experiment that encouraged participants to click certain links.

Grinstein and Kronrod found that praising with an assertive tone, and scolding with a non-assertive tone, were the most effective ways to deliver a message. To give just one example, in their controlled experiment, 56% of participants click on the desired link when they were given praise in an assertive tone, whereas only 44% did when they were praised in a non-assertive tone.

"Our findings suggest that an assertive tone intensifies, and a non-assertive tone attenuates, whatever is being said. Thus, our findings can possibly extend to persuasion contexts that go beyond specific communication tactics such as praising and scolding, for example, positive and negative framing," the authors write.