Originality in Academic Writing: The Blurry Lines Between Similarity, Plagiarism, and Paraphrasing

Across disciplines, most manuscripts submitted to academic journals undergo a plagiarism check as part of the evaluation process. Authors are widely aware of the industry’s intolerance for plagiarism; however, most of us don’t receive any specific education about what plagiarism is or how to avoid it. Here, we’ll discuss what actually constitutes plagiarism, understand the important differences between similarity and plagiarism, and discuss easy strategies to avoid the problem in the first place.

What actually is plagiarism?

The University of Oxford defines plagiarism as “presenting work or ideas from another source as your own… without full acknowledgement.” This is a fairly fundamental definition, and for most of us, this is the extent of our education on plagiarism.

When we think of plagiarism, we usually imagine an author intentionally copying and pasting text from another source. This form of plagiarism, called direct plagiarism, is actually fairly uncommon. More commonly, plagiarism takes the form of:

  • Accidental plagiarism. Citing the wrong source, misquoting, or unintentionally/coincidentally paraphrasing a source that you’ve never seen before is still considered plagiarism, even when done without intent.
  • Secondary source plagiarism. This is an interesting and challenging issue to tackle. This form of plagiarism refers to authors using a secondary source, but citing the works found in that source’s reference list—for example, finding information in a review but citing the initial/primary study instead, not the review itself. This misattribution “fails to give appropriate credit to the work of the authors of a secondary source and… gives a false image of the amount of review that went into research.
  • Self-plagiarism. There’s still an ongoing debate over the acceptability of reusing one’s own previous work, with differing answers depending on the context. It’s widely agreed that reusing the same figure, for example, in multiple articles without correct attribution to the original publication is unethical; however, it’s less clear whether it’s acceptable to use the same verbatim abstract in a manuscript as you previously published as part of a conference poster. Copyright law can play a major factor in the permissibility of self-plagiarism in niche cases.
  • Improper paraphrasing plagiarism.Some of us have heard from teachers or peers that, to avoid plagiarism, all you need to do is “rewrite it in your own words.” However, this can be misleading, as there’s a fine line between proper and improper paraphrasing. Regardless of the specific language used, if the idea or message being communicated is not your own and is not cited, it’s still plagiarism.

Plagiarism vs similarity

Many publishers, including Elsevier, Wiley, and SpringerNature, perform plagiarism evaluations on all manuscripts they publish by using software iThenticate. However, ‘plagiarism evaluation’ through iThenticate is a bit of a misnomer: iThenticate checks for similarity, not plagiarism. Though the difference between the two is minor, their implications are entirely different.

Whereas plagiarism refers to an act of ethical misconduct, similarity refers to any portion of your paper that recognizably matches text found in previously published literature in iThenticate’s content database. Similarity can include text matches in a manuscript’s references, affiliations, and frequently used/standardized terms or language; it’s natural and nonproblematic, unlike plagiarism.

A similarity report, such as the one generated by iThenticate, is used by editors as a tool to investigate potential concerns for plagiarism. If an iThenticate similarity report flags large sections of text as similar to a previously published article, the editors can then use this as a starting point to evaluate whether the article is, in fact, plagiarized.

Strategies to avoid plagiarism

Being accused of plagiarism—especially direct, intentional plagiarism— can be a serious ethical issue, with long-term implications for your job prospects and career. The best way to avoid this issue is to use preventative measures, such as the ones discussed here.

  1. Educate yourself about what plagiarism truly is and how it occurs. If you’ve made it this far in the article, you’re already making great progress! Consider reviewing the sources cited in this article to continue your education.
  2. Start citing from the note-taking phase. Many times, accidental plagiarism is the result of forgetting the source of an idea or statistic during quick, shorthanded note-taking. To avoid this, start building your reference list from the beginning of your research phase. Consider adding a quick citation for every single line of text—including citing yourself for your own ideas! Reference management software like EndNote and Zotero are great tools for this.
  3. Understand proper and improper paraphrasing. Learn how to correctly paraphrase someone else’s work and the importance of citing your paraphrased text. If you come across a phrase of sentence that perfectly summarizes an idea, don’t be afraid to include it as a direct, cited quotation!
  4. Consider cultural differences in plagiarism policies. This article aligns with the United States’ view of plagiarism as a serious ethical offense. However, this isn’t the case in all countries. In some East Asian countries, for example, the concepts of universal knowledge and memorization to indicate respect leads to a wider cultural acceptance of instances that would be considered plagiarism in America. If you’re unsure about what the expectations are for a certain journal, it’s always recommended to ask the editors.
  5. Use a similarity checker. While a similarity review won’t directly identify plagiarism, it can be great as a final scan for any text you may have copied and pasted with the intention of removing but forgot to erase, and it can help pick up accidental plagiarism! If your institution doesn’t have access to iThenticate, Turnitin, or CrossRef, there are several free similarity scanners available online.