Developments of prolonged exposure in treatment effect of post-traumatic stress disorder and controlling dropout...

Prolonged exposure (PE) has been proved as an efficacious psychological treatment for post-traumatic stress disorder (PTSD). There are mainly two changed formats of PE: the modified PE (mPE) and the PE combined with drug (PE/d). Symptom reduction following these two PE training formats has been reported in the patients with PTSD. However, very little is focusing on the direct comparison of mPE + PE/d and PE. Therefore, this paper aims to compare the mPE + PE/d with PE on the PTSD treatment effect and the dropout rate directly through the meta-analysis. Eighteen studies with total sample size of 1,397 met the final inclusion criteria. The results showed that mPE + PE/d had significantly lower posttreatment PTSD severity than control group (relaxation, wait list, etc.). There was no significant difference between mPE + PE/d and PE on the posttreatment, the follow-up PTSD score, and the posttreatment dropout rate. Compared with PE, lower PTSD symptoms and marginally lower dropout rate following the treatment were observed in the PE/d group. PE/d yielded a significantly larger effect size than mPE when compared with PE on the posttreatment PTSD symptom severity. The significance of the above results would not be changed even if studies causing high heterogeneity were removed. Although PE/d enhanced treatment effect and lowered dropout rate when compared with PE, it was still insufficient to draw the conclusion that formats of adjustments would specifically improve the implementation of PE. Further studies are warranted to develop an easily accomplished and efficacy-guaranteeing PE programme for PTSD patients.