This systematic review and individual participant data meta-analysis (IPDMA) examined the overall effectiveness of eye movement desensitization and reprocessing (EMDR) in reducing posttraumatic stress disorder (PTSD) symptoms, achieving response and remission, and reducing treatment dropout among adults with PTSD compared to other psychological treatments. Additionally, we examined available participant-level moderators of the efficacy of EMDR.

This study included randomized controlled trials. Eligible studies were identified by a systematic search in PubMed, Embase, PsyclNFO, PTSDpubs, and CENTRAL. The target population was adults with above-threshold baseline PTSD symptoms. Trials were eligible if at least 70% of study participants had been diagnosed with PTSD using a structured clinical interview. Primary outcomes included PTSD symptom severity, treatment response, and PTSD remission. Treatment dropout was a secondary outcome. The systematic search retrieved 15 eligible randomized controlled trials (RCTs); 8 of these 15 were able to be included in this IPDMA (346 patients). Comparator treatments included relaxation therapy, emotional freedom technique, trauma-focused cognitive behavioral psychotherapies, and REM-desensitization.

One-stage IPDMA found no significant difference between EMDR and other psychological treatments in reducing PTSD symptom severity (β = −0.24), achieving response (β = 0.86), attaining remission (β = 1.05), or reducing treatment dropout rates (β = −0.25). Moderator analyses found unemployed participants receiving EMDR had higher PTSD symptom severity at the post-test, and males were more likely to drop out of EMDR treatment than females.

The current study found no significant difference between EMDR and other psychological treatments. We found some indication of the moderating effects of gender and employment status.

Post-traumatic stress disorder (PTSD) has been reported in 90% of chemical warfare victims in previous studies. An individual's traumatic experience(s) may affect the lives of other family members as well. This cross-sectional case–control study compared the prevalence of PTSD symptoms in the husbands, the secondary PTSD symptoms in the wives and also aimed to identify if there was an association between the PTSD symptoms of the couples in the case group. Cases were 150 husband–wife couples where husbands were civilians exposed to chemical warfare; the controls were 156 husband–wife couples where there was no such exposure. Both cases and controls were recruited from Sardasht in Iran; this Kurdish city was attacked by four 250 kg sulphur mustard warheads in June 1987.

Across three sets of cut-off points for the Mississippi Scale for Combat-Related PTSD symptomotology (<120 and ⩾121; <106 and ⩾107; and <65, 65–130 and > 130) wives in the case group demonstrated higher rates of PTSD symptoms than did those in the control group; the difference was statistically significant. Furthermore, husbands in the case group had a significantly higher overall mean score (123.0 (s.d. = 17.2)) than the husbands in the control group (112.3 (s.d. = 21.7); P<0.001, t = 4.80). There was no statistically significant association between the overall PTSD score of the husbands in the case group with that of their wives (P = 0.274, correlation coefficient 0.092).

Husbands who were exposed to the chemical agents reported higher PTSD symptoms and there were higher rates of PTSD symptoms among the wives of individuals who were exposed to chemical warfare. Study results suggest the need for coordinated treatments, policy efforts and interventions to improve the wellbeing of chemical warfare victims and their caregiver wives.