Self-plagiarism is a contentious issue in higher education, research and scholarly publishing contexts. The practice is problematic because it disrupts scientific publishing by over-emphasizing results, increasing journal publication costs, and artificially inflating journal impact, among other consequences. We hypothesized that there was a dearth of empirical studies on the topic of self-plagiarism, with an over-abundance of editorial and commentary articles based on anecdotal evidence. The research question was: What typologies of evidence characterize the literature on self-plagiarism in scholarly and research journals? We conducted a scoping review, using the search terms "self-plagiarism" and "self-plagiarism" (hyphenated), consulting five social sciences research databases, supplemented by a manual search for articles, resulting in over 5900 results. After removing duplicates and excluding non-scholarly sources, we arrived at a data set of 133 sources, with publication dates ranging from 1968 to 2017. With an interrater reliability of over 93% between two researchers, our typological analysis revealed 47 sources (34.3%) were editorials; 41 (29.9%) were conceptual research (including teaching cases); 16 (11.7%) were editorial responses; 12 (8.6%) were secondary research; and only 8 sources (5.8%) were primary research. There is little guidance in the available literature to graduate students or their professors about how to disentangle the complexities of self-plagiarism. With primary and secondary research combined accounting for 14.4% of overall contributions to the data set, and primary research constituting only 6% of overall contributions, we conclude with a call for more empirical evidence on the topic to support contributions to the scholarly dialogue.