Wednesday, January 23, 2008

How many papers are just duplicates?

Study hints at plagiarism and re-publication in biomedical papers.

As many as 200,000 of the 17 million articles in the Medline database might be duplicates, either plagiarized or republished by the same author in different journals, according to a commentary published in Nature today1.

Mounir Errami and Harold ‘Skip’ Garner at the The University of Texas Southwestern Medical Center in Dallas, used text-matching software to look for duplicate or highly-similar abstracts in more than 62,000 randomly selected Medline abstracts published since 1995. They hit on 421 possible duplicates.

After manual inspection they estimated that 0.04% of the 62,000 articles might be plagiarized, and 1.35% duplicates with the same author. These percentages are lower than those calculated by similar previous studies. As yet, the researchers aren't sure why that is.

A thorough examination of apparent duplicates is always essential, they add, to verify whether papers are in fact plagiarised or resubmitted articles, or simply false positives. Some cases of duplication may also be done innocently. The ultimate decision has to be made by an authoritative body such as a journal's editors or an ethics board, they note.

Published online 23 January 2008 | Nature | doi:10.1038/news.2008.520