He adds, "All of us in our professional lives should inject a little more reflection in what we're doing, and reappraise regularly on whether what we're doing is based on the most solid evidence. That would go a long way."
Prasad's study was conducted with researchers at Yale University, Northwestern University, Lankenau Medical Center in Philadelphia, George Washington University, University of Maryland Medical Center and the University of Chicago.
They reviewed 2,044 articles published between 2001 and 2010, and selected 1,344 that concerned a medical practice. Of these, 981 examined a new medical practice and 363 tested an established practice. Of these 1,344, 947 had positive findings, but 397 were negative findings.
Of these 1,344, 756 suggested a medical practice should replace an older standard of care, 165 found that a new practice failed to surpass an older practice, 146 found that a current medical practice was actually inferior to a prior standard and the remaining 138 reaffirmed the older practice.
"Looking at all the examples we put together, the unifying theme is that the most common reason for things being found not to work is that they were actually adopted based on poor quality evidence," Prasad says.