Cognitive Behavior and Interpersonal Therapy are 25% Less Effective than

“We need to seriously consider publishing all completed studies”, whether encouraging or not, said Jelte Wicherts, an associate professor in the department of methodology and statistics at Tilburg University in the Netherlands, who was not involved in the study. However, of the 36 studies that showed antidepressants in a negative light, 61% were not published, while 31% were “spun” to make them appear positive.

Publication bias may have led psychiatrists and psychologists to be too optimistic about both talk therapy and drug treatment, Hollon says.

For their study, Hollon and colleagues set out to investigate whether psychotherapy – a treatment that is frequently offered to patients with mild to moderate MDD – may also have been subject to publication bias.

Psychotherapy is not as effective at treating depression as scientists once thought, according to a Vanderbilt University researcher’s study published Wednesday.

Of the 55 studies that had received NIH grants, 13 had not been published.

Building on earlier research that found a similar overestimation effect for pharmacological treatments for depression, the authors performed an extensive scouring of all proposed studies funded by the National Institutes of Health (NIH) from 1972 to 2008 that explicitly measured how effective any one psychotherapy was for major depression, so long as it was meant to be a randomized, controlled trial that recruited adults aged 18 or older.

Hollon’s team contacted the researchers who conducted these 13 studies to inquire about their results and then conducted meta-analyses of both the published and unpublished data.

So Turner was happy to join Hollon and other researchers interested in finding out whether the psychotherapy research had the same bias as drug research.

“The efficacy of psychological interventions for depression has been overestimated in the published literature, just as it has been for pharmacotherapy”, the researchers wrote in their study.

The findings mirror what researchers have previously observed with antidepressants and other drugs.

This raises once again the problem of publishing: studies that test out a hypothesis or a treatment and don’t come out positive simply don’t get published by journals, and this is a problem.

Hollon explains that, although studies are assessed through peer review, there are certain loopholes that allow the benefits of treatments to be overstated and possible risks to be understated. “The consumers of this skewed information are health care providers and, ultimately, their patients”.