The aim of this article is to present the findings concerning scientific fraud that have appeared in case reports. Deliberate scientific fraud does exist. The fact that most of the documented cases have occured in Anglo-Saxon countries seems to indicate, not that Anglo-Saxons are more prone to scientific fraud, but rather that they have been more successful in bringing it to light. Since 1974. 72 cares have been reported in which there was either conclusive evidence or else a strong presumption of fraud: one case in Switzerland, one in Canada, four in Australia, 14 in Great Britain and 52 in the United States Fraud is estimated to affect 2-5% of clinical research trials. Referees and renders do not set out to track fraud. The American Commission has proposed the terms ''misappropriation, interference, misrepresentation ''to define fraud. Voluntary fraud is hidden and its detection delayed. In well-known cares, more than 5 years elapsed before the information reached the scientific community. Whistle blowers must sustain a determined effort to denounce fraud over a period of 1-3 gears if they are to trigger an investigation. Some whistle blowers have themselves been accused of fraud because their claims proved so embarrassing. Fraud can [end to severe accidents and generate expenditure that those responsible, or the institutions they work for, will never pay back. Frauders are usually motivated by the desire for material gain or the desire to become well-known. The motivating factor may be personal enrichment, or a need for funds for a not-for-profit association People found guilty of fraud always have good excuses. Some simply do not realize that they have done. A knowledge of research methodology and critical appraisal methods help to prevent fraud. Good clinical, laboratory and manufacturing practice can help to prevent misconduct and trickery. Audits and inspections are another essential means of combating fraud.
