Data behind the publication (under review): Making headlines: An analysis of US government-funded cancer research mentioned in online media Background: Considerable resources are devoted to producing knowledge about cancer, which in turn is disseminated to policymakers, practitioners, and the public. Online media are a key dissemination channel for cancer research. Yet which cancer research receives media attention is not well understood. Understanding the characteristics of journal articles that receive media attention is crucial to optimize research dissemination. Methods: This cross-sectional study examines journal articles on cancer funded by the US government published in 2016, using data from PubMed and Altmetric to determine whether an article received online media attention. Frequencies and proportions were calculated to describe the cancer types and continuum stages covered in journal articles. Results: 16.8% of articles published on US government-funded research were covered in the media. Published journal articles addressed all common cancers. Roughly one-fourth to one-fifth of journal articles within each cancer category received online media attention. Media mentions were disproportionate to actual burden of each cancer type (ie, incidence and mortality), with breast cancer articles receiving the most media mentions. Cancer prevention and control articles received less online media attention than diagnosis or therapy articles. Conclusion: Findings revealed a mismatch between prevalent cancers and cancers highlighted in the media. Further, journal articles on cancer control and prevention received less media attention than other cancer continuum stages. Media mentions were not proportional to actual public cancer burden nor volume of scientific publications in each cancer category. Result highlight a need for continued research on the role of media, especially online media, in research dissemination. TBA: - SPSS code