Plagiarism, from the verb plagiarize, defined in the Concise Oxford Dictionary as "take and use (the thoughts, writings, inventions, etc., of another person) as one's own", is a hot issue in scientific publishing these days, and has provoked much recent discussion via journal articles, editorials and newsgroups. Entering the word 'plagiarism" into a PubMed search generates 505 hits, 121 published between January 2005 and May 2007.

There are 3 basic types, and in most cases there is intent to deceive: to deceive colleagues, to deceive readers, to deceive employers, to deceive funding bodies. The most serious form is the outright copying of research work. Duplicate publication, or self-plagiarism, is another form where the intention to deceive is the main purpose, either to boost the author' reputation or for the purposes of gaining promotion or a position.

Appropriating portions of text (sentences or paragraphs) without citing sources is probably the commonest type of plagiarism encountered in scientific reporting. In some cases this is due to carelessness in keeping records of sources; in others it is downright laziness. When the author is a non-native speaker, lifting whole tracts of text is often seen as an easy solution to the problem of producing a suitable Introduction or Discussion for a research paper.

What does this mean to the original author whose paper is then denied citation? In a milieu where "number of times cited" is considered an indication of the importance of a study, not only words, but also reputation have been stolen.

What does it mean for the author who copies text? It can also lead to loss of reputation: generally, those reading a paper work in the same field and will read as much as possible in that field. Coming across tracts that seem familiar and recognizing that they have been plagiarized will cast doubt on the originality of the rest of the paper, and consequently other research by the same authors. It also involves violation of copyright: most journal publishers, including the World Health Organization, own the copyright to the papers they publish.

The result of plagiarism, distortion of the scientific record, is not a trivial matter. In biomedical research, especially, this can have serious implications for patients in that it can boost the evidence for or against a particular medical treatment/intervention. For this reason, journals and editors have a responsibility to eliminate all forms of plagiarism