Although several commercial plagiarism detection software packages exist, the majority of US publishers allow the company Turnitin to access their database of published articles. Now, due to efficient search engines, online publishing, and software algorithms, journals increasingly utilize software that can efficiently scan thousands of manuscripts in seconds, matching submitted text to already published text. In the past, editorial offices have essentially relied upon chance detection by reviewers or editors to discover that submitted work had been previously published. However, doing so places a difficult burden on editors and publishers, only partially mitigated by existing informatics approaches designed to detect plagiarism. It is crucial that unacceptable copying be detected to preserve the integrity of the scientific literature. Plagiarism is a chronic and troublesome issue for scientific journals. The use of commercial plagiarism detection software can be optimized by selecting a cutoff score that reflects desired sensitivity and specificity.
Plagiarism was a common occurrence among manuscripts submitted for publication to a major American specialty medical journal and most manuscripts with plagiarized material were submitted from countries in which English was not an official language. The cutoff score maximizing both sensitivity and specificity was 15 % (sensitivity 84.8 % and specificity 80.5 %). Using the most commonly employed commercial plagiarism detection software, sensitivity and specificity were studied with regard to the generated plagiarism score. In 400 consecutively submitted manuscripts, 17 % of submissions contained unacceptable levels of plagiarized material with 82 % of plagiarized manuscripts submitted from countries where English was not an official language.
Commercial plagiarism detection software was utilized and its use was optimized. We manually curated submitted manuscripts and deemed an article contained plagiarism if one sentence had 80 % of the words copied from another published paper. In this study, the extent of plagiarism in manuscripts submitted to a major specialty medical journal was documented. However, its detection is time consuming and difficult, presenting challenges to editors and publishers who are entrusted with ensuring the integrity of published literature. Plagiarism is common and threatens the integrity of the scientific literature.