Are local teachers or nutrition experts perceived as more effective among Brazilian high school students?

A preliminary experimental study was conducted among 322 high school students in the Amazon region of Brazil to determine whether locally-trained teachers (high similarity/low expertise) or outside nutrition experts (high expertise/low similarity) would more effectively influence food choice attitudes and behavior. Subjects were randomly assigned to a control group or one of four treatment groups in which participants read a nutrition message and one of four accompanying author descriptions (high communicator similarity/high expertise, high similarity/low expertise, low similarity/high expertise, low similarity/low expertise). Subjects then responded to food choice attitude and behavior scale items. ANOVAs revealed only perceived similarity significantly influenced attitude and behavior. Thus, training local Brazilian nutrition educators perceived to be highly similar to Brazilian adolescents may be more cost-effective than recruiting nutrition experts. This study's consistency with studies conducted among Kenyan and American adolescents suggests perceived communicator similarity is a critical factor in international adolescent nutrition education.