Cancer is now the second leading cause of death for Americans, behind heart disease. By current estimates, up to two thirds of cancer diagnoses could be avoided or prevented with behavior changes such as the adoption of healthier lifestyles. One way that individuals learn about cancer is through the news media. Of all of the sources of health information available to consumers, news media rank among the most accessible and trusted sources; however, little is known about how cancer-related messages in the news media can affect consumers. Most studies focus on aggregate trends or other sources of health information instead of the news media. At the same time, self- and response-efficacy are two widely used variables in health research. Perceptions of self-efficacy relate to an individual's knowledge of how to perform a health behavior (e.g., a skin cancer self-exam) and his or her degree of confidence in performing that behavior. Perceptions of response efficacy relate to the extent to which an individual believes performing the behavior can prevent or mitigate some undesired health outcome (e.g., dying from skin cancer). This experiment looks at how messages about self-efficacy and response efficacy influence individuals' attitudes toward the behavior and behavioral intention, two key predictors of behavioral performance. In this study, six news stories about cancer were manipulated to contain both types of efficacy messages, self-efficacy messages only, response efficacy messages only, or no efficacy messages, for a total of 24 news stories. In a between-subjects, multiple-message design, participants were randomly assigned to read one of the 24 news stories and report the attitudes toward the behavior, behavioral intentions, perceived susceptibility, perceived severity, cancer anxiety, perceived self-efficacy, perceived response efficacy, and demographic descriptors. Results revealed few significant relationships; efficacy messages had little effect on participant attitudes or behavioral intentions, except in certain situations. The conditions where both types of efficacy messages were present had more of an impact on attitudes toward the behavior compared to conditions where no efficacy messages were present, but the same effect did not emerge for behavioral intentions. No mediating influences of perceived self-efficacy, perceived response efficacy, perceived susceptibility, perceived severity, or cancer anxiety emerged. Individuals with higher levels of perceived susceptibility reported stronger behavioral intentions to perform the behavior, but this was unrelated to efficacy message condition. Reasons for the lack of significant results and ethical considerations of this research are explored. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]