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.
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.