Remember that study showing vaccines were linked to autism? The time scientists claimed to have cloned human embryonic stem cells? Or that simple, easy way that was supposed to revolutionize the creation of such stem cells?Those were all frauds published in the world’s top scientific journals — The Lancet, Science and Nature. The vaccine scare has been associated with a surge in cases of measles, some of them deadly.Every day, on average, a scientific paper is retracted because of misconduct. Two percent of scientists admit to tinkering with their data in some kind of improper way. That number might appear small, but remember: Researchers publish some 2 million articles a year, often with taxpayer funding. In each of the last few years, the Office of Research Integrity, part of the United States Department of Health and Human Services, has sanctioned a dozen or so scientists for misconduct ranging from plagiarism to fabrication of results.