A recent study, published in the journal PLOS ONE, showed that talk therapy for the treatment of depression may not be as effective as it has been shown in other research. According to the authors, this suggests that the psychology field still approaches a phenomenon called as “publication bias”.

Publication bias is described in the study as “the tendency for authors to submit, or journals to accept, manuscripts for publication based on the direction or strength of the study’s findings”. In other words, only studies that present strong results are being published, which ultimately leads to an overestimation of treatment effects.

According to the paper, all researchers have a “fiduciary and ethical duty to provide a return on the public’s investment by making a good faith effort to publish.” Image: Colleen Arnold

“This doesn’t mean that psychotherapy doesn’t work. Psychotherapy does work. It just doesn’t work as well as you would think from reading the scientific literature.” said psychologist Steven Hollon, from Vanderbilt University, in a released statement.

That is the case with studies related to depression. According to the US Centers for Disease and Prevention, depression is one of the most common and disabling illnesses in the United States. In fact, among 8 million Americans seek some sort of medical care for treating this illness. It affects about 8 percent of people aged 12 or older during a two-week period.

It has been said that talk therapy is one of the most effective ways for treating this illness. However, Ellen Driessen from the VU University Amsterdam’s, along with Steven Hollom from Vanderbilt University, decided to study this issue. They conducted a similar research in 2008, but regarding antidepressant drugs.

For the study, they reviewed 55 grants awarded by the National Institute of Health (NIH) to fund clinical trials of psychological treatments for depression between 1972 and 2008. According to the findings, 13 of those studies were not published due to poor results. After that, they got in touch with the researchers who had conducted the unpublished studies, but only managed to receive the data of 11 of them.

“We therefore call upon the NIH to expand its Public Access Policy so that the public can have full, not partial, access,” researchers reportedly said.

When they analyzed these data, they found that there was a 24 percent overestimation of the effectiveness of antidepressants for the treatment of depression, which also matches with the results of his early research in 2008.

Although this does not show talk therapy to be ineffective to treat depression, it does show the importance of publishing all the studies made, even the ones that do not through desired results.

Researchers emphasize the difficulty of treating depression as a whole. It is very hard to judge the effectiveness of a treatment since the disorder is very unstable. However, hiding results of studies does not help science to advance.

These findings match with other made two months ago when a group of researchers replicated about 100 past psychological studies and found out that one third of them provide the original results, making these studies to appear unreliable.

Source: PLOG ONE