Interpreting Similarity Check Reports

Through our participation in Crossref, Hindawi uses iThenticate software to highlight text overlap between a submitted manuscript and existing literature. Occasionally, our Editorial Office will send you a similarity report to assess whether there is inappropriate re-use of wording.

The report will contain a calculation of the overall percentage of reuse. This number should be taken with caution. A high percentage is not necessarily unacceptable, but only an indication that there might be plagiarism or redundancy. It is important to look through the report to see the sources of overlap and where sections of overlap occur.

Things you should consider:

  • The nature of the overlap – are the similarities fragmentary or in blocks? Are complete sentences or paragraphs copied from previous works?
  • Where the overlap occurs – duplication of background ideas in the introduction or common methods may be considered less significant than duplication of the discussion or conclusions
  • Data duplication – this is almost never acceptable without appropriate citation
  • Citation - was the source of the text overlap cited and discussed?
  • Authorship - was the source written by one or more of the same authors as the Hindawi submission? If so, the concern might be with copyright or redundant publication rather than plagiarism. Some overlap is allowed, e.g. with the authors’ own preprint or thesis, if those sources are mentioned.
  • Could the software have miscalculated the similarity, e.g. by including large chunks of text that are properly contained within quotation marks or by flagging similarities in the references?

If you feel the level of similarity requires attention, you can request that the authors rewrite sections of their manuscript and cite any missing references prior to peer review. It may be that you regard the manuscript as too plagiarized to be further considered, and therefore it should be rejected.

If you have any questions regarding the iThenticate similarity report or to discuss concerns about plagiarism in an article, feel free to contact

For more information, see: