Publication bias in medical journals is a well-known phenomenon. The latest evidence is explained in Frederik Joelving’s intriguing piece for Reuters Health, “Journal experts prefer ‘splashy’ findings.” Excerpts:
Given similar, fabricated reports that compared two treatments, reviewers from a pair of top-line orthopedic journals recommended publishing the fake results in 97 percent of cases when there was a difference between treatments, but only in 80 percent of cases when there was no difference.
“No-difference studies affect practice just as much as positive ones, but they aren’t as sexy,” said Dr. Seth Leopold of the University of Washington in Seattle, who led the new research. “Something splashy, something new, is more exciting to everybody.”
The problem is that favoring studies that identify, say, a new drug as superior to an older one will make the newer drug seem better than it really is.
As a consequence, when doctors scour the scientific literature about a given treatment, they don’t see the whole picture.
“We felt that these results really confirm beyond any reasonable doubt that positive bias occurs at the level of peer review. That is critically important for the integrity of the medical literature,” he added.