In the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders criteria for posttraumatic stress disorder (PTSD) incorporate trauma-related cognitions. This adaptation of the criteria has consequences for the treatment of PTSD. Until now, comprehensive information about the effect of psychotherapy on trauma-related cognitions has been lacking. Therefore, the goal of our meta-analysis was to determine which psychotherapy most effectively reduces trauma-related cognitions. Our literature search for randomized controlled trials resulted in 16 studies with data from 994 participants. We found significant effect sizes favoring trauma-focused cognitive-behavioral therapy as compared to nonactive or active nontrauma-focused control conditions of Hedges' g = 1.21, 95% CI [0.69, 1.72], p < .001 and g = 0.36, 95% CI [0.09, 0.63], p = .009, respectively. Treatment conditions with elements of cognitive restructuring and treatment conditions with elements of exposure, but no cognitive restructuring reduced trauma-related cognitions almost to the same degree. Treatments with cognitive restructuring had small advantages over treatments without cognitive restructuring. We concluded that trauma-focused cognitive-behavioral therapy effectively reduces trauma-related cognitions. Treatments comprising either combinations of cognitive restructuring and imaginal exposure and in vivo exposure, or imaginal exposure and in vivo exposure alone showed the largest effects.
Diehle, J., Schmitt, K., Daams, J.G., Boer, F., & Lindauer, R.J. (2014). Effects of psychotherapy on trauma-related cognitions in posttraumatic stress disorder: a meta-analysis. Journal of Traumatic Stress, 27(3), 257-264. doi: 10.1002/jts.21924.