The advent of computer and mobile devices revolutionarily changes the way of communication. Technologies on mobile devices, websites and applications provide users the ability of more engagement and interactions with the content. Communication on the internet is distinguishable from communication on traditional media, such as print media and television. Traditional media allow users to have a linear way of processing information while digital media provide a curvilinear way for users to perform actions and process information based on their own choices and preferences. Is this form of communication and information processing more effective and efficient for users to absorb information online, especially health information? Websites for health topics, such as skin cancer prevention and awareness, have a variety of ways in which they can present health information to audience members. The present study used skin cancer and sun protection as a health topic to explore how different types of interactivity on the health websites influenced user engagement, information processing, attitudes, and behavioral intentions. This study (N=287) employed a 2 (modality interactivity: high vs. low) x 2 (message interactivity: high vs. low) between-subjects online experiment to evaluate effects of two types of interactivity, modality interactivity and message interactivity, on interface assessment of a skin cancer website, perceived credibility, knowledge, affective trust, cognitive trust, heuristic and systematic processing, attitudes toward skin cancer information and attitude toward the health website, and behavioral intention to use sunscreen in the future, intention to recommend the website to others, and intention to visit health websites in the future. Findings suggested that modality interactivity influenced behavioral intentions via its prior effects on perceived knowledge, affective trust, and attitudes toward the skin cancer information. Message interactivity affected behavioral intentions through its prior effects on perceived knowledge. Message interactivity led to more systematic processing while modality interactivity had a positive influence on attitudes toward the website and skin cancer information. Implications for designing health websites and health intervention content are discussed
