The lifetime prevalence of posttraumatic stress disorder (PTSD) ranges from 1 to 14 percent in the general population. Diagnosis is based on criteria that address hallmark symptoms of the disorder from re-experiencing the trauma to hyperarousal, emotional numbing, and avoidance of memories, thoughts, or feelings associated with the event. PTSD is particularly prevalent in vulnerable populations and comorbid with substance use disorders, serious mental illness, or both. Psychological treatment options are more strongly recommended than pharmacological treatment by the American Psychological Association (APA); however, the efficacy of psychotherapy is less studied in vulnerable populations for fear that substance use or mental health outcomes will worsen. Prolonged exposure (PE) therapy and cognitive processing therapy (CPT) are the most investigated forms of cognitive behavioral therapy (CBT) in vulnerable populations and involve overcoming the trauma through repeated exposure for PE or processing with a clinician for CPT. A review of all randomized controlled trials (RCTs) that have evaluated the effect of either form of CBT on non-combat PTSD, substance use disorder (SUD), and mental health outcomes found that PE administered alongside SUD treatment had the greatest positive impact on PTSD and SUD outcomes. PE also had a better impact than CPT on PTSD outcomes in individuals with PTSD and serious mental illness (SMI); however, neither form of CBT performed substantially better than the other with respect to mental health outcomes. In future studies, the impact of psychological treatments on PTSD and other health outcomes needs to be assessed on the same variables in larger populations of vulnerable individuals that are inclusive and representative of those receiving care for SUD and SMI in community health care settings.

The effectiveness of memory specificity training (MeST) was compared with standard cognitive processing therapy (CPT) in treatment of individuals with posttraumatic stress disorder. Eighteen adults aged 18-36 were randomly assigned to the MeST intervention (n = 9) or to the active control group (n = 9) of CPT. Both treatments were administered in group format across 6 weeks. MeST consisted of 6 weekly sessions, while CPT consisted of 12 biweekly sessions. The trial was undertaken in the Psychology Clinic of the University of North Texas, with randomization to conditions accomplished via computer random number generator. The primary outcome measure was change in PTSD symptoms post-treatment from baseline. Sixteen individuals (13 women and 3 men; MeST n = 8 and CPT n = 8) completed treatment and their data was analyzed. MeST significantly decreased PTSD symptomology at post-treatment and these results were maintained at 3 months post-treatment. MeST was found to be as effective as the established CPT intervention at reducing PTSD symptomology. Both MeST and CPT significantly increased participants' ability to specify memories upon retrieval at post-treatment, with results maintained at follow-up. There were no significant effects of MeST or CPT in ability to increase overall controlled cognitive processing at post-treatment or follow-up. No individual in either group reported any adverse effects during treatment or at 3 months follow-up. MeST appears to hold promise as an efficacious treatment option for PTSD. MeST was as effective as CPT in reducing symptoms of PTSD, but required only half the number of treatment sessions to accomplish these gains. Replication of these findings in larger samples is encouraged.

The current study takes an initial step toward deriving a method for empirically based, theory-driven treatment matching in a military population suffering from PTSD. Along with the more overt symptoms of PTSD (e.g., persistent hyperarousal), secondary cognitive symptoms have also been shown to be significantly associated with avoidance and intrusive symptoms, as well as contribute to functional impairment. Based on the factor analytic and treatment literature for PTSD, it appears that there are two central mechanisms associated with beneficial therapeutic change that underlies both CPT and PE treatments (i.e., habituation, changes in cognitions). Additionally, different traumatic events and peritraumatic responses may be associated with unique symptom profiles and may necessitate targeted treatment. The present study proposes a novel approach to treatment matching based on the factor structure of PTSD and underlying mechanisms of treatment response. More broadly, this paper provides evidence for a broader understanding of peritraumatic responses and the potential implications of these responses for symptom profiles and illness trajectories.