Message source credibility in drug education.

A questionnaire was administered to 1,734 university students and 381 high school students enrolled in drug education programs, surveying student opinions about the credibility of various proposed message sources. Five sets of proposed message sources were presented to each subject; each set consisted of one proposed source category that did not require a college education, one source that required a baccalaureate degree, and one that was a doctoral-level, university-trained professional with relevant experience. "Doctoral-level, university-trained professionals with relevant experience" was found to be the message source deemed most credible by both groups of students.