Health information is increasingly being shared online not just by credentialed sources such as physicians or health organizations, but also by patients with personal experience with a health concern. This dissertation proposes a new measure of vigilance-avoidance, or tendency to approach or avoid threatening stimuli, in order to understand how…

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…