No one is denying that talking things out with a therapist can be helpful for those with depression. But, like antidepressants, psychotherapy's usefulness may be overstated, researchers say, per the New York Times—by as much as 25%, finds a study in PLOS One. "This doesn't mean that psychotherapy doesn't work," says study co-author Steven Hollon. "It just doesn't work as well as you would think from reading the scientific literature." And that scientific literature may be partly to blame, the Times notes. Due to publication bias, studies that have more positive outcomes are more likely to end up published. "It's like flipping a bunch of coins and only keeping the ones that come up heads," Hollon says in a press release.
Researchers tracked down all NIH grants awarded from 1972 to 2008 for studies examining "talk therapy"—such as interpersonal and cognitive behavior therapies—to treat depression. Of the 55 studies found, 13 (which mainly showed no psychotherapy benefits) were never published. When the researchers tracked down the original data for those studies and included it in their calculations, talk therapy's effectiveness dropped by about 25%—"the same [bias] as you see in the pharma trials" for antidepressants, co-author Erick Turner tells the Times. That doesn't negate either drugs or therapy for treating depression, though the Times writes that it's a "difference that suggests that hundreds of thousands of patients are less likely to benefit." (A recent study found a common antidepressant is unsafe for teens.)