The purpose of the present study was to examine, via meta-analysis, the efficacy of third wave therapies in reducing posttraumatic stress (PTS) symptoms. A secondary aim was to identify whether treatment efficacy was moderated by treatment type, treatment duration, use of exposure, use of intent-to-treat samples, and treatment format (i.e., individual, group, both). Risk of bias was also assessed. A literature search returned 37 studies with a pooled sample of 1268 participants that met study inclusion criteria. The mean differences between pre- and post-treatment PTS symptoms were estimated using a random effects model (i.e., uncontrolled effect). Additionally, in a subset of studies that utilized a control condition, a controlled effect in which pre- to post-treatment PTS symptom changes accounted for symptom changes in the control condition was calculated. The overall uncontrolled effect of third wave therapies in reducing PTS symptoms was medium to large (Hedges’ g = 0.88 [0.72–1.03]). Treatment type, use of intent-to-treat analysis, inclusion of exposure, and format moderated the uncontrolled effect, but treatment duration did not. The controlled effect of third wave therapies was small to large in size (Hedges’ g = 0.50 [0.20−0.80]). Findings suggest that third wave therapies demonstrate enough promise in treating individuals with PTS symptoms to warrant further investigation. Implications and suggestions for future third wave research are discussed.

本研究的目的是通过荟萃分析检查第三波疗法在减轻创伤后应激障碍（PTS）症状方面的功效。第二个目的是确定是否通过治疗类型，治疗持续时间，暴露量的使用，意向性治疗样品的使用和治疗形式（即，个体，组，两者）来调节治疗效果。还评估了偏见的风险。文献检索返回了符合研究纳入标准的1268名参与者的37个研究样本。使用随机效应模型（即不受控制的效应）估算治疗前和治疗后PTS症状之间的平均差异。此外，在利用控制条件的一部分研究中，计算出一种可控制的效果，在该效果中，治疗前至治疗后PTS症状的变化占对照条件下症状的变化。第三波疗法在减轻PTS症状方面的总体不受控制的效果为中到大（Hedges'g  = 0.88 [0.72-1.03]）。治疗类型，使用意向分析，包括暴露和形式减轻了无法控制的效果，但治疗持续时间却没有。第三波疗法的控制效果，从小到大尺寸（树篱克= 0.50 [0.20-0.80]）。研究结果表明，第三波疗法在治疗患有PTS症状的个体方面显示出足够的前景，值得进一步研究。讨论了对未来第三波研究的启示和建议。