http://www.futurity.org/scientific-literature-psychotherapy-1034072/
“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,” says Steven Hollon, a psychology professor at Vanderbilt University who co-authored the study with colleagues from Oregon Health and Science University, VU University Amsterdam, and the University of Groningen.
The basic problem arises because clinical studies of the treatments for depression with more positive outcomes are more likely to be published than studies with less favorable results.
“It’s like flipping a bunch of coins and only keeping the ones that come up heads,” says Hollon.