Questionable Research Practices in Experimental Communication Research: A Systematic Analysis From 1980 to 2013

Questionable research practices (QRPs) pose a major threat to any scientific discipline. This article analyzes QRPs with a content analysis of more than three decades of published experimental research in four flagship communication journals: Journal of Communication, Communication Research, Journalism & Mass Communication Quarterly, and Media Psychology. Findings reveal indications of small and insufficiently justified sample sizes, a lack of reported effect sizes, an indiscriminate removal of cases and items, an increasing inflation of p-values directly below p <.05, and a rising share of verified (as opposed to falsified) hypotheses. Implications for authors, reviewers, and editors are discussed.