Loving-Kindness Meditation vs Cognitive Processing Therapy for Posttraumatic Stress Disorder Among Veterans

Key Points Question Is group loving-kindness meditation noninferior to group cognitive processing therapy for treatment of posttraumatic stress disorder (PTSD) among veterans? Findings In this randomized clinical trial, 184 veterans with PTSD were assigned to group loving-kindness meditation or group cognitive processing therapy; the differences in the decrease from baseline to 6-month follow-up for measures of PTSD and depression were very similar and within predefined margins considered not meaningfully different. Attendance was better for loving-kindness meditation. Meaning This study adds to the evidence indicating that interventions without a specific focus on trauma, including meditation-based interventions, can yield results similar to trauma-focused therapies.

improvement in the major symptom clusters of PTSD, although the magnitude of the treatment effect is 99 modest. 18 Prazosin, an alpha-antagonist, reduces trauma-related nightmares and has also been found to have 100 a significant effect on all of the PTSD symptom clusters. 18 Despite these and other pharmacologic agents, 101 many persons with PTSD continue to experience persistent PTSD symptoms, as well as anger, difficulties with 102 interpersonal relationships, shame, and grief. 6 Psychotherapeutic techniques are often combined with 103 pharmacotherapy in the treatment of PTSD. Prolonged exposure (PE) therapy facilitates emotional processing 104 of the traumatic event, helping individuals to develop less phobic responses to internal and external trauma 105 cues. 19 However, PE is difficult for many Veterans to complete, as evidenced by a high dropout rate (38%). 20 106 PE may also fail to address the entire realm of posttraumatic psychopathology including anger control, 107 interpersonal difficulties or grief. 6 In addition, PE and EMDR are usually administered by an individual therapist 108 rather than as a group treatment, which limits the ability to efficiently deliver these interventions to large 109 numbers of persons. Cognitive Processing Therapy (CPT) can be delivered either individually or in group 110 settings and has some initial support for efficacy in addressing PTSD among Veterans. In addition to concerns 111 about dropout for some Veterans, another potential shortcoming of current treatment for PTSD is the lack of 112 empirical data to guide treatment for persons with multiple psychiatric diagnoses. Psychiatric conditions other 113 than PTSD commonly co-occur with PTSD, 16 yet persons with multiple psychiatric diagnoses have often been 114 excluded from clinical trials. A further limitation is that many studies employed interventions delivered by expert 115 PTSD therapists with extensive experience, raising the question of whether the favorable results from these 116 clinical studies can be generalized. 20

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The VA has invested considerable resources to disseminate both PE and CPT through national roll-118 outs to increase the likelihood that Veterans will have access to these empirically supported treatments.

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Although research published in 2004 indicated that neither of these empirically supported treatments were 120 widely utilized by therapists within the VA, 21 more recent findings suggest that the roll-outs have met with initial 121 success and plans are in place to monitor future penetration of PE and CPT within the VA. 22 These efforts will 122 no doubt relieve a great deal of suffering among Veterans with PTSD. However, given the large number of 123 Veterans with PTSD, many with significant comorbidities and not all of whom will benefit from or elect to 124 participate in PE or CPT, additional cost-effective treatments suitable for broad implementation are needed.
Evidence indicates that about 15% of the US adult population utilizes mind-body therapies, with a 158 group reported significantly greater positive emotions and were significantly less depressed at the end-point 159 assessment than the no-LKM group, even though both groups reported a similar frequency of negative 160 emotions day-to-day. They also found that positive emotions persisted after meditation sessions ended, and 161 that over time, repeated LKM practice produced a cumulative increase in positive emotions on subsequent 162 days, regardless of whether the individual had practiced meditation on that day. 9 A pilot study of LKM for 163 chronic low back pain by Carson et al compared a group that underwent LKM (n=18) with a group receiving 164 standard care (n = 22) and found that those in the LKM group reported lower pain ratings, less anger, and less 165 psychological distress (note: positive emotions do not appear to have been assessed). 29 Another study of LKM, 166 performed in a group of community participants, indicated that a single brief session of LKM training led to 167 increased self-esteem and sense of social connectedness relative to a control condition. 30 In a report of case 168 studies in which LKM was taught to persons with schizophrenia, LKM appeared to be of potential benefit for 169 persistent negative symptoms. 31

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In LKM practice, a person sits quietly and calls to mind a particular person (e.g., a good friend) and 171 focuses on bringing a sense of positive regard to that individual through a series of standard phrases invoking 172 the desire for safety, happiness, health, and ease or peace for them. Classically, four phrases are used, such 173 as: "may you be safe," "may you be happy," "may you be healthy," and "may your life unfold with ease." Next, 174 the person brings positive regard to other individuals or categories of people, including themselves, neutral 175 persons, and those who have caused difficulty or harm (see Approach section), changing the phrases as 176 needed (i.e., "may you be safe" becomes "may I be safe"). 32 This systematic development of kindness toward 177 self and others is intended to change the orientation to one's self, others, one's life experiences, and to result 178 in a broadening of the range of emotional responses and choices available. Loving-kindness practice has its 179 roots in the Buddhist tradition, but as described above an increasing number of studies have successfully 180 applied it as a non-religious practice. The phrase loving-kindness derives from the Pali word metta, which can be translated as "love" or "unconditional friendliness," or "loving-kindness," akin to the Greek word "agape," 182 which is typically translated as wide open unconditional love. The words loving-kindness are intended to 183 describe an emotional state that is not a sentimental love or a feeling of passion. Rather, it can be described as 184 an unconditional friendliness, benevolence, and openness toward experienceeven difficult experience.

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It can be postulated that the intentional cultivation of kindness and acceptance promoted in LKM 186 practice will positively influence multiple aspects of recovery from trauma. Although the factors described 187 below might also be developed through mindfulness practice (e.g., in MBSR through breathing meditation),

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LKM is a distinct form of practice that is often considered more accessible and therefore more helpful to

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second key postulate of the broaden-and-build theory is that the broadened mindset associated with positive 236 emotions leads to the building of enduring personal resources. These personal resources are thought to arise through new thought-action sequences such as play, curiosity, and openness to new situations and ideas, as 238 well as new social interactions. Personal resources built may include cognitive resources (e.g., the ability to 239 mindfully attend to the present moment), psychological (e.g., a sense of purpose in life, self-acceptance or self-240 compassion, or a sense of environmental mastery) social (e.g., improved ability to give and receive social 241 support) or physical (e.g., reduced susceptibility to stress-associated illnesses). 9 According to the broaden-242 and-build theory, people who have developed these personal resources are more likely to successfully 243 navigate life's challenges and live happier, healthier lives.

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There is growing evidence in support of the broaden-and-build theory. The 'broaden' hypothesis

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Identification of active components of treatments is a priority for treatment research. 38 The proposed study will 261 evaluate potential mediators of change thought to be specific to each intervention.

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LKM: We will evaluate whether enhanced self-compassion mediates change in PTSD and depression for 263 LKM. Self-compassion can be considered a healthy form of self-acceptance. Neff defines self-compassion as 264 comprised of three facets: (1) treating oneself kindly and without harsh judgment in the setting of pain and 265 failure, (2) perceiving that mistakes and hardships are part of the common human experience rather than 266 isolating, and (3) maintaining mindful, non-judgmental awareness of thoughts and feelings rather than or 267 overidentifying with them. 39 Self-compassion is distinct from self-esteem, which is typically defined as an 268 evaluative process in which one's abilities and characteristics are compared to standards. 39 Self-compassion is 269 also distinct from self-centeredness, because self-compassion acknowledges the ubiquity of pain and hardship 270 among humans. LKM is considered a method to enhance self-compassion. As suggested by our pilot work 271 with LKM, we hypothesize that for those in the LKM arm of the study self-compassion will mediate improved 272 outcomes for persons with PTSD such that changes in self-compassion will both temporally precede changes 273 in PTSD and when they are statistically controlled, the changes in PTSD will be attenuated. There is initial 274 support for this hypothesis from the literature. 40,41 In an analysis of people with a history of major depression 275 randomized to a mindfulness intervention or maintenance antidepressants, enhanced self-compassion 276 mediated the relationship between participation in mindfulness training and reduced depressive symptoms at 277 follow-up. 41 The possibility of a key role for self-compassion is consistent with emerging theory and evidence 278 that self-compassion is adaptive in the setting of painful or difficult thoughts and feelings. 28,40 It is also possible 279 that changes self-compassion will mediate changes in PTSD for those in the CPT-C arm of the study, but we 280 anticipate that these effects will be less robust than for those in the LKM arm of the study.  intervention, Cognitive Therapy for PTSD, and not CPT, the finding suggests that CPT is also likely to result in such changes in beliefs and appraisals that in turn mediate PTSD symptom reduction. The proposed project 293 would afford the opportunity to evaluate whether this is the case for Veterans who participate in group-based 294 CPT-C. 45 We will also be able to assess whether reductions in maladaptive cognitions also mediates 295 reductions in PTSD for those who receive training in LKM.

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The Approach: What LKM Is and Isn't

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Having provided an overview of what LKM is, we also believe it is important to delineate it from other 298 approaches with which it may be confused. First, although both LKM and mindfulness meditation practices 299 involve sitting meditation, typically with closed eyes and an initial focus on the breath, they differ in several 300 respects. Mindfulness meditation cultivates the ability to pay attention, without judgment in the present 301 moment, whereas LKM specifically develops the ability to experience kindness, warmth, and openheartedness 302 toward self and others. The intentionality of LKM is toward developing the ability to experience positive 303 emotions, rather than developing non-judgmental awareness. Second, LKM differs from intercessory prayer.

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Although in LKM practice the phrases repeated express the intention of wellbeing for self and others (see 305 below), it is made clear that there is no expectation that the LKM phrases will actually benefit others. Instead, it 306 is made explicit that the goal of LKM practice is to benefit oneself, such that in developing the capacity to 307 experience kindness toward self and others, the person who holds this intention actually benefits.

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Unfortunately the intercessory prayer literature has not evaluated whether praying for others has a salutary 309 effect on the people doing the praying, though research on spiritual involvement, including prayer activity, has 310 found that Veterans with greater spiritual involvement have better physical and mental health than those with 311 less spiritual involvement. 46 Third, although LKM involves the repetition of phrases, it is distinct from mantram 312 repetition practices, which involve bringing attention to a repeated phrase or word that facilitates humans suffer and all desire happiness, which is fostered by LKM, is likely to lead to forgiveness. In addition,

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LKM is also distinct from the practice of verbalizing positive affirmations. While there may be some overlap with 325 regard to the shared emphasis on positivity, affirmations tend to be stated as though they are definite personal 326 qualities and are intended to strengthen self-confidence (e.g., "I am a good, kind person"), whereas LKM is 327 usually stated as an invitation or request that is intended to tap into the intention for kindness and compassion 328 for oneself and for others (e.g., "may I be safe from harm;" "may you be happy and healthy"). Importantly, 329 another way that LKM is distinct from positive affirmations is that LKM is a meditation practice intended to 330 broaden attention and allow positive emotions to remain in awareness for sustained periods of time.

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The LKM course follows the instructions for LKM as described by Salzberg. 32 During the12 meetings 341 the ten to twelve group participants will receive instruction from two expert meditation teachers (who will co-342 teach the sessions) in the practice of LKM, including both in-session practice of LKM and group discussions.

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The intervention is designed to allow patients to adopt skills and techniques they can continue to practice 344 without the need for an ongoing relationship with a therapist. LKM is taught in a non-religious format. A class-345 by-class outline is provided in the participant workbook (Appendix 3).

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In order to help develop concentration, a necessary component of LKM practice, the first two sessions 347 focus on cultivating mindful attention of one's breath. The primary LKM practice begins in week 3, and involves sitting in a comfortable, relaxed position with closed eyes or a neutral visual focus and then bringing to mind 349 various categories of beingsself and others. The meditator is then asked to gently repeat phrases to the

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A version of CPT that does not include writing a trauma narrative has also been evaluated, CPT-C, and 380 has been found to be associated with more rapid improvement than standard CPT-C as well as comparable 381 outcomes to standard CPT. 43 The elimination of the trauma narrative makes CPT-C more conducive to a 382 group-based delivery platform as it reduces the risk that group participants will be traumatized by one another's 383 stories. CPT-C has recently been shown to be effective in a group format for Veterans, active duty military 384 personnel, and reservists with PTSD. 5 In a randomized controlled trial (N=107), group CPT-C was compared to 385 present-centered therapy (PCT) and the former found to be more effective than the latter in reducing PTSD  Veterans by experienced leaders, and fidelity coding from audiotapes will evaluate protocol adherence.

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Participants will complete brief take home paper assessments weekly for the 12-week duration of the active 418 treatment phase to assess key outcomes, potential mediators of change, and completion of homework 419 assignments. All participants in each study condition will complete an in-person baseline assessment, which 420 will be repeated immediately after the treatment phase as well as 3-and 6-months post-intervention. In-421 person assessments will be performed by a blinded assessor.

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Use of an Active Control Arm: The active control will account for the non-specific elements of LKM (e.g.,

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group support, positive expectancy). The proposed control arm is CPT-C, which will provide the same amount 424 of clinician-exposure time (it is also a group-based, 12-week duration, 90-minute per session program). Similar 425 to LKM, CPT-C is taught by experienced instructors who believe in the benefit of the program; allegiance of the 426 researcher/therapist has been shown to be strong predictor of treatment outcomes. 55 CPT-C therefore 427 contains key elements of an active controlit is structurally similar to LKM (thus controlling for non-specific 428 elements of the intervention) and given that it is an accepted PTSD treatment, CPT-C will foster positive 429 expectation for intervention success by both therapists and patients. Each of these elements has been dependence disorder other than alcohol; alcohol involvement that poses a safety concern (i.e., currently 454 drinking and has a past year history of alcohol-related seizures or delirium tremens), suicide attempt or suicidal 455 ideation with intent or plan, self-harm in the past month, a psychotic disorder, uncontrolled bipolar disorder, 456 chart diagnoses of borderline personality disorder, antisocial personality disorder, or dementia in-patient admission for psychiatric reasons within the past month, prior participation in LKM, or CPT. Medication, 458 supportive individual or group counseling, case management, and self-help programs will be allowed 459 concurrently and assessed as potential covariates.

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Telephone Screen. Veterans who contact the Project Manager will be provided an overview of the study.

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Veterans who remain interested will undergo a 15-20-minute telephone screen to ascertain basic 463 inclusion/exclusion criteria.

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In-person Screen and Baseline Assessment. Following informed consent, participants will undergo a 2-465 hour assessment. The Study Assessor will conduct standardized interviews for the presence of exclusionary 466 disorders (relevant subsections of the MINI International Neuropsychiatric Interview) and for diagnosing PTSD 467 (Clinician Administered PTSD Survey; CAPS). 57 Self-report measures will be administered on a VA-approved 468 computer. Those who are eligible to continue the study will receive their randomization assignment within 469 approximately one week and will begin either LKM or CPT-C within one month.

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Follow-up Assessments. Participants will complete a post-treatment assessment within a week of 474 completing LKM or CPT-C, and will repeat the assessment battery 3-and 6-months thereafter.

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We will utilize a blocked randomization approach stratified by symptom severity on PTSD because our pilot 477 studies indicate that those who score in the severe range (60 or higher) 57 on the PCL decrease their PTSD 478 symptoms more than those with less severe PTSD but are still more symptomatic at immediate post-test.

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Baseline severity of PTSD will be dichotomized based on CAPS-5 scores > 37 Because our pilot data did not 480 suggest that severity of depression moderated outcome, we will not include that in the randomization 481 stratification. Similarly, we chose not to stratify on gender because our pilot data indicate that this factor is not 482 predictive of PTSD symptoms at follow-up. A series of randomization tables will be constructed and will be 483 maintained by the research coordinator. Subjects will be randomized in small blocks of varying size using 484 concealed allocation, after the baseline assessment and within two weeks before the next study cohort is set to 485 begin treatment.

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Each class meeting will begin with either a brief mindfulness meditation (weeks 1 and 2) or an LKM 489 meditation followed by an opportunity for participants to discuss their experiences integrating LKM class 490 material into their daily lives. New material will then be presented, typically introducing a new category of 491 beings (i.e., benefactor, oneself, strangers, etc.) and particular challenges associated with working with that 492 category of beings will be discussed. The class will then practice LKM incorporating the new category and then 493 discuss the experience. At the end of each class the homework for the next week will be presented and class 494 will end with another brief LKM practice. Participants will be provided with an LKM meditation CD and a 495 workbook to accompany the class. (See appendix 3, LKM manual, for additional details). An overview of the 496 class schedule is provided below: 497 Classes 1 and 2 provide an introduction to in mindfulness meditation.

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Class 3 introduces LKM, including the LKM phrases and a description of the meaning of each phrase. Begin

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LKM practice toward a benefactor, which is defined as a person who has been kind or helpful and for whom 500 there is gratitude, and respect. Participants will be asked to recall the ways this benefactor has helped them, 501 and the goodness within this person.

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Class 4 introduces the theme of commitment to our own happiness as a basis for intimacy and connection with 503 self and others. Exercise: "Remembering the good within you" (Instructions: "For 10-15 minutes call to mind 504 something you have said or done that was a kind or good action"). Acknowledgement and discussion of the 505 finding that LKM toward our self is often difficult. If participant is unable to practice LKM toward self, suggestion 506 of the concept that underlying all action is a desire to be happythis may provide a method of noticing 507 kindness toward oneself that already exists; this may act as a starting point for feeling positive emotion for 508 oneself. LKM toward benefactor and self with the 4 phrases. Introduction of walking meditation and the concept of a beloved friend (may be a person or an animal).

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Class 11 begins with discussion of LKM toward groups, with an emphasis on whether unconscious affinity or 538 bias was detected in the ability to practice LKM.

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Class 12 begins with discussion of walking meditation. Introduction of LKM for all beings. Discussion of 540 different categories of beings as appropriate for each personalive or dead, human or animal. Practice LKM 541 toward self, friend, benefactor, neutral person, difficult person, groups, toward all beings.

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Homework for those randomized to LKM homework will consist of 30 minutes of sitting or walking 543 mindfulness (first two weeks) or LKM meditation facilitated by CD recordings with new categories of beings 544 added as described above. Participants will also be instructed to identify opportunities for informal LKM 545 practice each week.

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CPT-C will be led by clinicians who will be contracted by the grant to deliver this service. The group co-548 leaders will all have completed the VA's CPT-C training and certification program or the equivalent in the 549 community. In addition, these clinicians will go through the necessary background checks and credentialing 550 procedures prior to having contact with any Veterans.

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Those assigned to CPT-C will attend weekly 90 minute group therapy sessions for 12 weeks. Treatment 552 will be provided in groups of 10 to 12 male and female Veterans with PTSD.

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Session 1 provides an introduction to CPT-C and education about both PTSD as a response to trauma and 554 how trauma exposure can lead to distorted thinking and beliefs. Patients are oriented to the Impact Statement 555 homework.

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Session 2 draws from the Impact Statement homework and reviews how patients are currently framing the 557 meaning of their index trauma with regard to its impact on their lives in the following areas: safety, trust, 558 power/control, esteem, and intimacy. The concept of trauma-related cognitive "stuck points" is introduced.

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Session 3 introduces a basic cognitive therapy overview of the relationship between thoughts and feelings 560 prompted by triggering events through the ABC sheet (A = activating event; B = beliefs; C = consequences).
Session 4 elaborates on the idea of "stuck points" (e.g., "I am damaged goods;" "I'm a failure because I 562 couldn't save my best buddy," etc.) that may have arisen as a result of the trauma exposure and each group 563 member is assisted in identifying their own specific "stuck points."

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Session 5 provides a standard list of challenging questions that patients use to help themselves identify stuck 565 points.

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Session 6 provides an overview of common patterns of problematic thinking (e.g., all/none thinking, confusing 567 feelings with facts, etc.). The Challenging Beliefs Worksheet is introduced in this session.

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Session 7 provides further instruction on the use of the Challenging Beliefs Worksheet.

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Session 8 reviews the safety module and patients are instructed to focus on at least one safety-related issue 570 when completing worksheets for homework.

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Session 9 reviews the trust module and patients are instructed to focus on at least one trust-related issue when 572 completing worksheets for homework.

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Session 10 reviews issues related to power/control and patients are instructed to focus on at least one 574 power/control-related issue when completing worksheets for homework.

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Session 11 reviews self-and other-esteem issues and patients are instructed to focus on at least one esteem-576 related issue when completing worksheets for homework and to write their final impact statement.

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Session 12 reviews intimacy issues and the patients' current sense of the event's meaning.

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Homework for those randomized to CPT-C will consist of 30 minutes of CPT-C-related homework 6 days a 579 week including writing an impact statement at the beginning and the end of treatment, completing CPT-C 580 worksheets, and completing exercises regarding safety, trust, power/control, esteem, and intimacy.

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Each of these teachers is employed as a WOC-status contract employee, and meets stringent foundational 588 teacher training requirements for MBSR, which we also apply to LKM teaching requirements: longstanding 589 practice of mindfulness and loving-kindness meditation, experience with a body-centered awareness practice, 590 attendance at silent mindfulness meditation retreats of at least 7 days duration, completion of the University of 591 MA Center for Mindfulness Residential Training/Retreat as well as a teacher practicum in MBSR. We believe 592 that these teacher training requirements and prior experience teaching MBSR will be directly applicable to 593 high-quality teaching of LKM.

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To assure quality control, Dr. David Kearney will review at least 2 early session tapes from each LKM 595 cohort to provide supervisory feedback. Teaching responsibilities will be shared by Carolyn McManus, PT, MA 596 and Jonas Batt, MA, MHC, both of whom currently teach LKM at VAPSHCS. They will co-teach the LKM 597 courses to provide different perspectives and gender balance across the facilitators. If either of these teachers 598 becomes unavailable, there are 3 additional experienced mindfulness and loving-kindness meditation teachers 599 who are currently teaching other meditation classes at VAPSHCS who will be available to teach LKM. A subset 600 of 20% of LKM classes will be coded for protocol adherence by two independent raters (see Appendix 5).

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Adherence and competence will be measured using treatment fidelity ratings based on the LKM curriculum.

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Our pool of undergraduate raters will be trained by Dr. Kearney, who will provide ongoing supervision 603 regarding fidelity ratings.

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CPT-C Fidelity. CPT-C group leaders selected to provide CPT-C will have completed either the VA's 605 national rollout dissemination training and certification process or the community equivalent, and thus will have 606 had at least 6 months of supervised experience delivering CPT-C. They will also be employed as WOC 607 contractors. The CPT-C supervisor will be Dr. Carie Rodgers is a national trainer in CPT for the VA National

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Center for PTSD who was trained by CPT originator, Dr. Patricia Resick and has extensive experience both 609 delivering group-based CPT-C herself within VHA and supervising others.. She will provide weekly supervision 610 based on both review of session tapes and oral reports from the group co-leaders to assure real-time quality 611 control of CPT-C delivery.

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A random subset of 20% of each group's 12 sessions will be coded for protocol adherence and 613 competence by two independent raters from our pool of undergraduate raters (see Appendix 6 for coding 614 forms). Adherence and competence will be measured using established published measures of CPT-C treatment fidelity. Raters will be trained by Dr. Galovski (CPT-C) with ongoing supervision provided by Dr.

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CAPS Interview Fidelity. The Study Assessor will a be master's level clinician who will undergo training on 618 the CAPS interview by Dr. Simpson. Dr. Simpson will sit in on at least 5% of the CAPS interviews to provide 619 ongoing supervision.

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Maintaining the Assessment Blind. The Study Assessor will be kept blind to participant condition: 621 participants will be reminded not to disclose treatment assignment, and other study personnel will avoid 622 communications that could provide such information.

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Procedures for Maximizing Retention. Participants will update contact information at each visit and will be 624 paid $20 for baseline, post-test, $30 for the 3-and 6-month assessments, and $5 per week for the 12 online 625 assessments. Participants who complete all assessments will be eligible for an additional $20 bonus.

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We have chosen the following measures in order to assess outcomes for the aims of this study,

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including PTSD symptomatology, depression, and potential mediators. The weekly monitoring phase will 644 record the amount of homework practice completed (for both LKM and CPT-C), in order to provide the ability to 645 assess whether homework practice is predictive of improved outcomes.

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PTSD Symptoms. Participants' PTSD symptomatology will be assessed using the Clinician-Administered 647 PTSD Scale (CAPS) and the PTSD checklist (PCL).

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The CAPS is the primary outcome measure. The CAPS requires a clinician to rate 17 diagnostic

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The PCL-C is a 17-item self-report measure that correlates highly with scores derived from the Clinician

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Administered PTSD Scale (CAPS). 63 The PCL has good internal consistency, item-total correlations, 662 concurrent and convergent validity, and test-retest reliability. Each item is rated by the patient on a scale of 1 663 to 5, and the total score of the PCL is calculated as the sum of the all the items. Higher scores reflect more severe PTSD. 59 The PCL will be administered during the weekly monitoring phase in order to allow 665 assessment of clinical outcomes as part of mediation analyses, and will be included at weekly time points 666 (post-LKM/CPT-C, 3-and 6-months) as a secondary outcome measure.

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Posttraumatic Cognitions Inventory (PTCI). 62 The PTCI is a 36-item measure that assesses trauma-related 694 thoughts and beliefs including negative cognitions about self, about the world, and self-blame. Items are rated 695 on a 7-point scale ranging from "totally disagree" to "totally agree." The PTCI has been found to discriminate 696 well between people who do and do not have PTSD and has been found to have good internal consistency, 697 test-retest reliability, and construct validity. The PTCI will be administered at baseline and follow-up time points 698 as a secondary outcome measure. The abbreviated 22-item version 44 will be collected weekly to assess 699 whether changes in posttraumatic cognitions mediate changes in the primary outcome measures.

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Weekly monitoring assessment protocol. Weekly assessment of type and duration of LKM and CPT-C 701 homework practices completed along with measures of PTSD and depression and the proposed intervention 702 mediators will be assessed weekly during the twelve weeks of LKM or CPT-C treatment. The weekly 703 assessments will be administered via take home paper assessment. (See Appendix 9 for weekly items.)

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Assessment of Usual VA Mental Health Care. In order to quantify the amount of VA mental health care that 705 study participants obtain during their involvement in the proposed study, data extraction from both the VA

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Corporate Data Warehouse (CDW) and from the computerized patient record system (CPRS). The number of 707 individual and group psychotherapy stopcodes and mental health medication management stopcodes will be 708 recorded for all participants for the period of time they are directly involved in LKM (and equivalent time period 709 for CPT-C) from the CDW. These numbers will be cross-checked via CPRS and CPRS therapy notes will be 710 assessed to determine whether study participants were involved in treatments for PTSD during their 711 involvement in LKM or the follow-up period (and equivalent time period for CPT-C). We will also use CPRS to 712 code for psychiatric and pain medication adjustments during study involvement.

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Data Analysis

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Overview. Before performing the primary analyses, outliers, shape of distributions, and associations 715 between outcomes will be determined. Covariates or propensity scores will be utilized to adjust for differences 716 if imbalances between treatment groups on key variables are identified. Gender and type of trauma will also be 717 considered as covariates. All analyses will be performed using an intention-to-treat sample as well as per 718 protocol analyses. Per protocol analyses are the preferred method for non-inferiority analyses, in order to avoid biasing the results toward no difference between groups, which could occur in intention-to-treat samples.

Power and Sample Size:
mediates change in CPT-C relative to LKM by examining the indirect effect of treatment condition (CPT-C vs.