Date of Award


Document Type

Open Access Thesis


School of Journalism and Mass Communications


College of Information and Communications

First Advisor

Brooke Weberling McKeever


Controversy about genetically modified (GM) food prevails on social media. Discussion about GM food includes the implementation of mandatory labeling as well as public concerns about potential health hazards posed by GM food. Previous studies mainly focus on traditional press and broadcast media, few investigate such controversial topics on social media. Interested in public opinion about this issue and possible influences of social media on public opinion, this study uses quantitative content analysis to examine the characteristics of user comments on a specific social media platform, YouTube. The purpose of the study is to investigate YouTube comments from several aspects, encompassing attributes, valence, sources cited to support opinions, motivation of commenting, along with other characteristics (uncertainty, interactivity, and hostility) embedded in these comments. In addition, the study also examines whether there are relationships between some of the variables mentioned above. Findings in this study showed that the most discussed issue related to GM food among YouTube users was informative education, and viewers were prone to comment in a negative tone. Interestingly, uncertainty manifested in the comments was associated with interactivity among commenters. Additionally, hostility toward GM food and mass media were highly associated with interactivity among commenters.