Study quality and effect-sizes - a metaanalysis of EMDR-treatment for posttraumatic stress disorder

Although the good efficacy of eye movement desensitization and reprocessing (EMDR) in the treatment of patients with PTSD is up to now documented by a number of studies, this new treatment technique is still the target of highly controversial critique. Our meta-analysis tries to answer the question of whether EMDR-therapy studies with higher quality standards achieve better results than others. Therefore, all published studies underwent a scoring procedure of study quality and effect sizes were computed. It can be shown that carefully planned studies, including treatment by well-trained therapists and with a sufficiently high number of treatment session achieve better results compared to studies with low methodological standards.