A surprising upsurge in the number of scientific papers that have had to be retracted because they were wrong or even fraudulent has journal editors and ethicists wringing their hands. The retracted papers are a small fraction of the vast flood of research published each year, but they offer a revealing glimpse of the pressures driving many scientists to improper conduct.

Last year, Nature, a leading scientific journal, calculated that published retractions had increased tenfold over the past decade — to more than 300 a year — even though the number of papers published rose only 44 percent. It attributed half of the retractions to embarrassing mistakes and half to “scientific misconduct” such as plagiarism, faked data and altered images.

Now a new study, published in the Proceedings of the National Academy of Sciences, has concluded that the degree of misconduct was even worse than previously thought. The authors analyzed more than 2,000 retracted papers in the biomedical and life sciences and found that misconduct was the reason for three-quarters of the retractions for which they could determine the cause.

The problem is global. Retracted papers were written in more than 50 countries, with most of the fraud or suspected fraud occurring in the United States, Germany, Japan and China. The problem may even be greater than the new estimates suggest, the authors say, because many journals don’t explain why an article was retracted — a failure that calls out for uniform guidelines.