Meta-analysis of eye movement desensitization and reprocessing efficacy studies in the treatment of PTSD
Eye Movement Desensitization and Reprocessing (EMDR) is a relatively new psychological therapy used in the treatment of PTSD and other disorders. EMDR is unique in that it combines sets of therapist-administered eye movements in conjunction with protocol-driven cognitive and affective processing related to past trauma. EMDR has become a controversial technique for reasons including a lack of explanation for why it works and stunning claims made for its efficacy in the literature. Despite a large amount of research over the past decade, EMDR has not before been studied meta-analytically in its own right.The present investigation used meta-analysis to examine the collection of EMDR PTSD studies available in the literature. The literature search resulted in a total of 21 studies, which met inclusion criteria. These primary studies in turn resulted in a collection of 118 effect sizes included in the analysis. Two separate analyses were conducted dependent on whether EMDR was compared to a no treatment control group or an alternative treatment control group. In addition to an overall estimate of the efficacy of EMDR in the treatment of PTSD represented through an effect size, five sub-hypotheses were investigated. First, it was hypothesized that EMDR would be more efficacious with a non-combat population than with combat-related PTSD. The second sub-hypothesis was that there would be significantly larger treatment effects associated with verbal report measures than with physiological outcome measures used in EMDR PTSD studies. Third, it was hypothesized that earlier EMDR studies would show larger treatment effects than more recent EMDR studies. The fourth sub-hypothesis concerned treatment dosage. It was hypothesized that there would not be significant differences based on the number of treatment sessions administered. Finally, it was hypothesized that the bilateral stimulation component of EMDR therapy would not contribute significantly to treatment effects. The analysis consisted of generating effect sizes in the form of standardized difference scores on the various outcome measures. Effect sizes were then grouped according to independent variable categories and averaged together. Before testing for between-group differences, homogeneity testing was completed.
Original Work Citation
Alto, C. (2001, November). Meta-analysis of eye movement desensitization and reprocessing efficacy studies in the treatment of PTSD. Dissertation Abstracts International: Section B: The Sciences and Engineering, 62(5-B), 2474
“Meta-analysis of eye movement desensitization and reprocessing efficacy studies in the treatment of PTSD,” Francine Shapiro Library, accessed November 23, 2020, https://emdria.omeka.net/items/show/15447.