Our long-term goal is to provide rapid and sustained reductions of trauma and cognitive-related symptoms among Special Operations personnel with PTSD or subthreshold PTSD. The primary objective of this project is to examine the effectiveness of massed PTSD treatment (i.e., CPT and EMDR) in "real-world" military settings. CPT and EMDR are both empirically supported psychotherapies for PTSD. To accomplish this objective, we will enroll military personnel meeting diagnostic criteria for PTSD or subthreshold PTSD (i.e., meeting threshold levels for 3 of 4 symptom criteria).

Posttraumatic stress disorder (PTSD) is considered one of the "signature injuries" of military operations and is the most frequently diagnosed mental health condition among active-duty military personnel. PTSD is associated with a host of psychological problems (i.e., intrusions, avoidance, negative alterations in cognition/mood, and hyperarousal) and negative outcomes (i.e., occupational and marital dissatisfaction, violence, alcohol and substance abuse, and suicide).1-3 PTSD has also been correlated with poorer cognitive performance across various domains including attention, working memory, processing speed, and executive functioning.4,5 These psychological problems and cognitive impairments significantly impact military personnel's deployment readiness and overall quality of life.

Numerous randomized clinical trials support the efficacy of trauma-focused treatments like cognitive processing therapy (CPT) with multiple populations including active-duty military personnel.6-8 For this reason, CPT is one of three individual manualized trauma-focused psychotherapies that is strongly recommended for the treatment of PTSD by the VA/DOD Clinical Practice Guideline for the Management of Posttraumatic Stress Disorder and Acute Stress Disorder.9 Recent advances in PTSD treatment have shown that the effects of CPT on PTSD symptom reduction and remission are retained when the treatment is delivered in a "massed" format, which entails daily therapy sessions during a 2-3 week window instead of the traditional schedule of one session per week for multiple months.16,23 Massed CPT therefore achieves similar reductions in PTSD symptoms within a much shorter timeframe. Our team has shown, for instance, that over 70% of military personnel and veterans who received CPT in this format no longer met criteria for a PTSD diagnosis at treatment end.10,11 As compared to conventional therapy delivered weekly, massed trauma therapy has higher treatment retention and treatment completion.12 Massed models are also believed to reduce distraction, avoidance, and de-motivation that typically occurs between weekly sessions.13 Meeting with a therapist daily may also increase commitment to therapy due to a greater sense of support.14 Therefore, this strategy would allow increased access to therapy due to higher patient throughput, while providing patients with rapid and sustained symptom reduction, through improved treatment engagement and improved long-term outcomes.

Despite massed CPT's considerable promise, the effectiveness of this delivery model in real-world military settings remains poorly understood because previous research has only been conducted in highly controlled settings using specially trained research therapists who are closely monitored for protocol fidelity and reduced caseloads. The effectiveness of massed CPT when implemented in real-world military settings when delivered by military behavioral health professionals working in busy clinics with high caseloads, multiple competing work demands, and limited time to pursue case consultation and clinical supervision remains unknown, limiting our understanding of how previous research findings will translate to practice settings within a busy military operational environment. These possible barriers to effective implementation are magnified in Special Operations Forces (SOF) units, which typically have a greater number of deployments and often experience more intense combat than conventional forces-two factors associated with higher prevalence of PTSD.15,16 This is especially true for active-duty military personnel, who show attenuated treatment response as compared to civilians.17,18 Recent research has suggested that over 50% of service members retain their PTSD diagnosis after completing weekly CPT.7 PTSD symptom persistence may be explained by insufficient engagement of key causal factors: first, CPT may not induce enough change in relevant causal factors for recovery to occur, implicating the need for higher "doses" of therapy; second, CPT may induce change in only some, but not enough, causal factors, implicating the need for multiple (or different) treatments that target a broader range of causal factors. Supporting the first possibility is research showing that extending the length of CPT by adding more sessions can improve overall rates of recovery.19,20 In an earlier clinical trial of weekly CPT, for instance, 38.7% of active-duty military personnel who completed CPT scheduled twice weekly achieved good end-state by the twelfth and final session and another 20% reached good end-state following additional CPT sessions.19 Critically, 41.3% of CPT completers did not reach good end-state despite receiving 24 sessions of CPT (double CPT's typical "dose"), lending some support for the second possibility: CPT induces change in some, but not enough, causal factors. For this latter subgroup of patients, switching to a different trauma therapy that targets different causal factors may be indicated. Treatment switching is a common strategy in routine clinical practice when patients do not respond to an initial first line treatment. To our knowledge, the effectiveness of switching from one trauma therapy to another has never been investigated. As a result, there are currently no evidence-based decision rules to guide clinician and patient choice regarding "next steps" when patients do not benefit from CPT or any other trauma-focused therapy. This study will therefore be the first to investigate a critical question commonly asked by clinicians and patients: if a patient has not fully recovered from PTSD by the end of a first-line treatment like CPT, should the clinician continue CPT or should they instead switch to a different treatment modality? PTSD is often examined through a psychological lens, however due to the complex relationship between emotional and cognitive processes, there is an increased interest in examining the unique role that cognitive impairment plays in the development and maintenance of PTSD symptoms.22 Due to the frequency of poor PTSD treatment response, active military personnel frequently experience lingering cognitive impairments that may be due to PTSD. These cognitive impairments in turn often hinder recovery from PTSD by negatively affecting treatment response. The most robust findings suggest cognitive impairments in the domains of learning, executive functioning, processing speed, attention, and working memory in individuals with PTSD.4,5 Previous research suggests that cognitive impairments in individuals with PTSD can improve4, however data is limited, especially in active-duty military personnel.

Treatments that provide rapid and sustained reduction from psychological symptoms and cognitive impairments are direly needed, especially in specialized military populations and in "real-world" military settings. Pilot data collected by our team indicate that, as compared to usual care PTSD treatment, massed CPT treatment accelerates reductions in PTSD symptoms among military personnel and veterans. Other previous research suggests adaptive designs utilizing variable-length treatments may also improve treatment efficacy.19 This study will build on these promising findings by utilizing an innovative two-stage clinical trial design evaluating variable-length massed (i.e. daily) PTSD treatment administered under routine operational conditions. Military personnel who do not respond adequately to massed CPT treatment will be randomized to receive additional CPT or EMDR sessions. This design allows us to causally examine the efficacy of increasing treatment dose versus cross-treatment factors that target a broader range of mechanisms.

Inclusion Criteria:

-Treatment-seeking military personnel (i.e., any assigned or aligned JSOC personnel) who meet diagnostic criteria for PTSD or subthreshold PTSD (i.e., meeting diagnostic threshold for 3 of 4 symptom criteria who are (1) 18 years of age or older; (2) current diagnosis of PTSD or subthreshold PTSD (i.e. meeting diagnostic criteria for 3 of 4 symptom criteria, assessed using the DIAMOND); (3) current military personnel; (4) ability to speak and understand the English language; and (5) ability to complete the informed consent process

Exclusion Criteria:

• (1) substance use disorder requiring medical management; (2) imminent suicide risk warranting inpatient hospitalization or suicide-focused treatment; and (3) impaired mental status that precludes the ability to provide informed consent (e.g., intoxication, psychosis, mania).

Individual participant data available by request