What is political expression on social media anyway?: A systematic review

While a growing number of studies have examined political expression in the context of social media, fundamental questions remain about the communicative processes under study and the transformative role played by social media technologies. Accordingly, this paper undertakes a systematic review of quantitative studies that explicitly examine political expression on social media (N = 66) in order to clarify how past scholarship has conceptualized and measured political expression. In addition to identifying biases toward survey methodology (86.4% of studies) and the United States context (50% of studies), results indicate that political expression is often under-conceptualized and inconsistently measured. Yet the review highlights several ways in which this burgeoning literature provides opportunities to sharpen political expression as a distinctly useful concept for studying political communication in the digital age. To this end, we offer several recommendations for better theorization and measurement in this area of research.