A Tufts University School of Medicine reporter has realized that a pretty large amount of scientific findings are, well, wrong. This work follows on from a recent publication of his that found that a third of medical research articles published in major scientific journals and then cited over a thousand times in the literature are later contradicted or have major questions raised over them. The reasons are many: <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />
One of these factors is that many research studies are small. "The smaller the studies conducted in a scientific field, the less likely the research findings are to be true," says Ioannidis. Another problem is that in many scientific fields, the "effect sizes" (a measure of how much a risk factor such as smoking increases a person's risk of disease, or how much a treatment is likely to improve a disease) are small... Financial and other interests and prejudices can also lead to untrue results. And "the hotter a scientific field (with more scientific teams involved), the less likely the research findings are to be true," which may explain why we sometimes see "major excitement followed rapidly by severe disappointments in fields that draw wide attention."