Group Cognitive Behavior Therapy for Chronic Posttraumatic Stress Disorder: An Initial Randomized Pilot Study

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Behavior Therapy 40 (2009) 82 – 92

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Group Cognitive Behavior Therapy for Chronic Posttraumatic Stress Disorder: An Initial Randomized Pilot Study J. Gayle Beck,aUniversity at Buffalo–SUNY Scott F. Coffey,bUniversity of Mississippi David W. Foy,cPepperdine University Terence M. Keane,dNational Center for PTSD, VA Boston Healthcare System, Boston University School of Medicine Edward B. Blanchard,eUniversity at Albany–SUNY

Individuals with posttraumatic stress disorder (PTSD) related to a serious motor vehicle accident were randomly assigned to either group cognitive behavioral treatment (GCBT) or a minimum contact comparison group (MCC). Compared to the MCC participants (n = 16), individuals who completed GCBT (n = 17) showed significant reductions in PTSD symptoms, whether assessed using clinical interview or a self-report measure. Among treatment completers, 88.3% of GCBT participants did not satisfy criteria for PTSD at posttreatment assessment, relative to 31.3% of the MCC participants. Examination of anxiety, depression, and pain measures did not show a unique advantage of GCBT. Treatment-related gains were maintained over a 3-month follow-up interval. Patients reported satisfaction with GCBT, and attrition from this treatment was comparable with individually administered CBTs. Results are discussed in light of modifications necessitated by the group treatment format, with suggestions for future study of this group intervention.

We appreciate the assistance and cooperation of our participants, without whom this work would not have been possible. A big note of appreciation is extended to the doctoral students who worked on this project: Sarah Palyo, Berglind Gudmundsdottir, Luana Miller, DeMond Grant, and Joshua Clapp; to Marcy Brimo, CSW-R, who assisted as a therapist; and to Jillian Shipherd, Ph.D., who assisted with diagnostic reliability. This work was supported in part by a grant from the National Institute of Mental Health (MH64777). Address correspondence to Gayle Beck, Ph.D., Department of Psychology, University of Memphis, Memphis, TN 38152; e-mail: [email protected]. 0005-7894/08/0082–0092$1.00/0 © 2008 Association for Behavioral and Cognitive Therapies. Published by Elsevier Ltd. All rights reserved.

IN THE GENERAL POPULATION, posttraumatic stress disorder (PTSD) has an estimated lifetime prevalence of between 5% and 10% (Kessler, Sonnega, Bromet, Hughes, & Nelson, 1995; Kessler et al., 2005). As noted by Norris (1992), motor vehicle accidents (MVAs) are one of the leading causes of PTSD in civilians. In addition to PTSD, a number of other psychological and physical problems often are present after an MVA, including mood disturbances (e.g., Blanchard, Hickling, Taylor, & Loos, 1995), additional anxiety disorders (e.g., Kessler et al., 1995), and chronic pain from injuries sustained during the MVA (e.g., J. G. Beck, Gudmundsdottir, & Shipherd, 2003). Thus, the emotional toll of road crashes is pronounced, particularly in light of the fact that over 2 million people are injured in serious MVAs yearly (U.S. Department of Transportation, 2004). Fortunately, attention has been focused on the treatment of PTSD among survivors of serious MVAs, with promising results. As reviewed by Blanchard & Hickling (2004), initial reports of the treatment of PTSD among MVA survivors focused on imaginal and in vivo exposure with the first successful controlled trial (Fecteau & Nicki, 1999) published in 1999. Building on these findings, Blanchard & Hickling (2004) expanded their CBT program to 8 to 12 sessions. Specific interventions included exposure, relaxation training, cognitive interventions, and interventions to address estrangement, social isolation, and anger. To date, the efficacy of individual CBT has been examined in two randomized controlled

group cbt for ptsd trials. Blanchard et al. (2003) compared CBT with supportive psychotherapy and a wait-list condition. Ninety-eight individuals who met diagnostic criteria for PTSD or reported severe subsyndromal symptoms were included, all of whom had experienced their MVA between 6 and 24 months before the trial. Therapists were allowed flexibility in determining the number of sessions, with a mean in both conditions around 10. In the CBT condition, of the 21 individuals who met criteria for PTSD at pretest, 76% (n = 16) were not diagnosed with PTSD (PTSD−) at posttreatment. Within the supportive therapy condition, of the 21 individuals with PTSD at pretest, 48% (n = 10) were PTSD− at posttest. Within the wait-list condition, 24% (n = 5) of individuals with PTSD at pretest were PTSD−. These results were mirrored in self-report measures. Importantly, CBT produced concomitant changes in anxiety and depressive disorders, suggesting treatment generalization. Gains were maintained at 3-month follow-up. A second study was conducted recently by Maercker, Zöllner, Menning, Rabe, & Karl (2006) in which CBT containing similar components was compared with a wait-list condition. They modified the CBT treatment protocol to include greater emphasis on cognitive interventions, interventions to address guilt, and more discussion of positive outcomes that may have accrued from the MVA, including personal growth. These authors were careful to duplicate many aspects of the methodology of Blanchard et al. (2003) to allow comparison between trials. Results on both clinician and self-report measures were similar to those reported by Blanchard et al. (2003), with 75% (n = 9) of individuals who met criteria for PTSD at pretest being free of the disorder following CBT. Treatment-related gains were maintained at a 3month follow-up. In addition to this CBT approach, a related form of cognitive therapy has been developed that places greater emphasis on cognitive interventions, relative to the approach developed by Blanchard and Hickling. This intervention is designed to address negative appraisals that stem from the trauma, to correct autobiographical memory disturbance, and to reduce cognitive and behavioral avoidance (Ehlers & Clark, 2000). Ehlers et al. (2003) examined the efficacy of this approach, compared with a self-help bibliotherapy condition and a repeated assessment control condition, in 85 individuals who had experienced a serious MVA within the previous 6 months (acute PTSD). Results were supportive, indicating that 79% of participants were PTSD− following cognitive therapy,

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relative to 24% PTSD− in the self-help bibliotherapy condition and 30% PTSD− in the repeated assessment condition. Collectively, these studies provide convincing evidence for the effectiveness of cognitive behavioral approaches for the treatment of MVA-related PTSD. As positive as these treatment development efforts have been, individual therapy can be costly and difficult for patients to access. As discussed in the literature on health care economics (e.g., Miller & Magruder, 1999), individual therapies require considerable resources with respect to the availability of trained therapists. For disorders that are highly prevalent, group treatments offer the possibility of reaching more patients while using therapist time more efficiently. In fact, some health care systems rely almost exclusively on group treatments, given demand for services and limited number of providers (e.g., Fontana, Rosenheck, Spencer, & Gray, 2007). Group treatment of PTSD also may help to build social support networks and may facilitate treatment compliance. However, the available literature on group treatment of PTSD is mixed. For example, Foy et al. (2000) cautiously argue that group treatment for PTSD is potentially effective, recognizing that there are considerable differences across studies in methodological rigor. Six years later, the data on group treatment of PTSD continue to suggest effectiveness (Foy & Larson, 2006). An example of a methodologically rigorous study with mixed results was conducted by Schnurr & colleagues (2003). These investigators compared traumafocused group CBT (e.g., Foy et al., 2000) with a nonspecific group therapy. Vietnam veterans with chronic PTSD (N = 360) who might not tolerate or comply with individual exposure therapy were recruited into the study. The group therapy consisted of 30 weekly sessions, followed by 5 monthly booster sessions. Intent-to-treat analyses revealed no differences between the active and comparison treatment conditions. However, examination of the veterans who attended at least 24 active treatment sessions (n = 217) indicated superiority of trauma-focused group CBT over the comparison condition on avoidance and numbing symptoms. As discussed by Resick and other experts (e.g., Foy et al., 2000; Hickling & Blanchard, 1999; Resick & Schnicke, 1993), developing an efficacious group treatment for PTSD requires careful consideration of the process of intervention, as well as its content. One cannot simply conduct an individual treatment within a group setting, given the potential for significant emotional volatility among members of the group. Importantly, efforts

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to transport an individual treatment into a group setting without modification appear to diminish treatment effectiveness. For example, Taylor et al. (2001) examined individual patient responses to Blanchard and Hickling's CBT program when conducted in a group. As described by these authors, no modifications were made to the CBT. In this report, the overall treatment response was not strong, as only 19 of 50 patients (38%) no longer met criteria for PTSD after treatment. With these concerns in mind, Beck & Coffey (2005) described the adaptation of individual CBT to a group treatment setting. As part of the development effort, consideration was given to elements of individual treatment that would not translate easily into a group format. Starting with Blanchard and Hickling's CBT protocol, changes were made to the order of interventions, as well as strategies for conducting and discussing exposurebased interventions. As described in greater detail by Beck and Coffey, development efforts included strategies to enhance group cohesion, adapting exposure-based interventions so as to reduce the potential for worsening PTSD symptoms due to exposure to descriptions of others' traumas, and inclusion of treatment methods to handle anxiety caused by driving to the treatment session. In the current study, we report the results of an initial randomized clinical pilot study designed to compare the efficacy of Group Cognitive Behavior Therapy (GCBT) with a minimal contact comparison condition (MCC condition). Participants included individuals with MVA-related PTSD who were at least 6 months post-accident (chronic PTSD). We hypothesized that GCBT would be more effective in alleviating PTSD than the MCC condition and that gains would be maintained through a 3-month follow-up assessment.

Method participants Potential participants were recruited from pain clinics, physical therapists, chiropractors, and specialists in rehabilitation and internal medicine, as well as public service announcements. Individuals qualified for assessment if they had experienced an MVA involving actual or threatened death or serious injury at least 6 months prior to assessment and their emotional response included intense fear, helplessness, horror, or the perception that they would die (PTSD Criterion A; American Psychiatric Association, 2000). These features were evaluated using the MVA Interview (see below). Individuals involved in accidents that did not satisfy Criterion A were not evaluated. During a 24-month

interval, 186 individuals were scheduled for assessment, with 35 (18.8%) not completing the initial assessment. Individuals presenting with neurological impairment (n = 6), substance dependence and abuse in the 6 months preceding the assessment (n = 2), psychotic symptoms (n = 4), acute suicidality (n = 2), or medical conditions that prohibited participation (n = 2) were excluded. Individuals whose accidents occurred less than 6 months prior to assessment (n = 34) or who did not meet criteria for PTSD (n = 45) were not included. Of the 56 participants who qualified, 12 declined participation. No differences were noted between the final sample (n = 44) and those who declined participation (n = 12) on demographic variables, severity of PTSD, anxiety, or depression symptoms, or the presence of pain complaints (all p's N.05). The number of co-occurring anxiety and mood disorders is reported in Table 1. The final sample included 44 participants (36 female, 8 male) who ranged in age from 22 to 69 (mean = 43.3, SD = 12.8). The majority self-identified as Caucasian (88.6%, n = 39; African American, n = 4; Hispanic, n = 1), married (52.3%, n = 23; single, n = 8; cohabitating, n = 4; divorced or widowed, n = 5), having at least some college-level education (75%, n = 33; high school education only, n = 11), and either unemployed or on disability (54.4%, n = 24; employed full or part-time, n = 16; housewife, n = 3; retired, n = 1). Seventy-four percent of the sample had an annual household income of $50,000 or less. The majority of patients (n = 35, 80%) reported ongoing pain complaints from injuries sustained during the MVA. In these cases, pain caused significant lifestyle limitations, impairment, or significant distress. Average elapsed time after the MVA was 52.9 months (median = 15.5, SD = 100.10). The majority of the sample (n = 33, 75%) was engaged in MVA-related litigation and regularly using medication for pain and/or mood problems (n = 43, 98%). All provided informed consent prior to participation. To approximate clinical samples, we did not exclude individuals who had experienced other traumatic events in addition to the index MVA for which they sought treatment. Forty-five percent of the sample reported additional traumas, which included natural disasters, non-MVA accidents, sexual assault, and witnessing a violent death.

assessment of outcome Assessment of PTSD. PTSD was evaluated using both a clinician-administered and a self-report measure. The Clinician-Administered PTSD Scale (CAPS; Blake et al., 1990), a structured interview that assesses PTSD symptoms identified in the

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Table 1 Means (standard deviations in parentheses unless otherwise noted) for Group Cognitive Behavioral Therapy and Minimum Contact Comparison conditions at PRE, POST, and FU, with inclusion of effect sizes for Completer and Stability analyses GCBT n = 17

MCC n = 16

Effect size GCBT Effect size POST versus MCC at POST versus FU

Posttreatment

Followup a

Pretreatment

Posttreatment

Completers

GCBT completers only

28.9 (19.9) 8.4 (7.3) 11.1 (8.6) 9.5 (7.9) 0.9 (0.9) 0.7 (0.8) 1.3 (1.2) 0.95 (0.9)

19.7 (18.8) 5.2 (5.7) 7.2 (7.6) 7.3 (7.7) 0.7 (0.7) 0.6 (0.8) 0.9 (0.8) 0.78 (0.7)

57.8 (14.9) 19.0 (8.0) 21.9 (7.5) 16.9 (5.7) 2.2 (0.9) 1.8 (0.9) 2.5 (1.0) 2.10 (0.9)

49.4 (27.0) 15.4 (8.5) 20.9 (12.6) 13.1 (8.0) 1.9 (1.2) 1.5 (1.0) 2.3 (1.1) 1.91 (1.0)

0.84

0.35

0.87

0.33

0.89

0.35

0.43

0.24

1.04

0.01

0.83

0.01

0.83

0.19

0.96

0.12

Assessment of anxiety and depression No. of additional 1.4 0.5 anxiety disorders (0.9) (0.8) No. of depressive 0.4 0.1 disorders (0.5) (0.3) BAI 22.2 15.9 (14.6) (10.6) BDI-II 22.4 16.6 (10.7) (12.4)

0.9 (1.1) 0.2 (0.4) 13.5 (9.9) 15.1 (11.0)

1.5 (1.3) 0.4 (0.5) 24.1 (14.4) 27.2 (13.6)

1.3 (1.4) 0.3 (0.5) 23.3 (16.3) 26.2 (17.0)

0.69

0.33

0.70

0.18

0.53

0.06

0.63

0.02

Assessment of physical functioning and pain severity b ODI 47.1 38.7 34.2 (11.2) (18.7) (12.1) PS-MPI 52.2 47.7 42.6 (5.6) (8.8) (4.5)

51.2 (14.9) 48.8 (11.5)

50.2 (15.6) 45.2 (10.5)

0.66

0.07

0.57

0.41

Pretreatment Assessment of PTSD CAPS-Total 57.3 (15.5) CAPS 17.2 reexperiencing (7.2) CAPS avoidance/ 22.8 numbing (6.7) CAPS physiological 17.4 hyperarousal (6.5) IES-R intrusion 1.8 (0.8) IES-R avoidance 1.5 (0.8) IES-R physiological 1.8 hyperarousal (0.9) IES-R total 1.75 (0.7)

Note. GCBT = Group Cognitive Behavioral Treatment; MCC = Minimal Contact Comparison; CAPS = Clinician Administered PTSD Scale; IES-R = Impact of Event Schedule-Revised; BAI = Beck Anxiety Inventory; BDI-II = Beck Depression Inventory-II; ODI = Oswestry Disability Index; PS-MPI = Pain subscale, Multiaxial Pain Inventory. a At FU, the sample size for GCBT was 15. b For these measures, sample sizes are as follows: GCBT n = 11, MCC n = 14 for the PRE/POST comparisons. For the POST/FU comparisons, the sample size is 9.

DSM-IV, was used and anchored to the index trauma (MVA). The CAPS includes standardized questions to determine frequency and intensity of each symptom, assessed in the preceding month, using a 5-point Likert-type scale. The total severity score for the CAPS (CAPS-Total) is computed by summing the frequency and intensity ratings for each symptom. Additionally, symptom cluster scores (Re-Experiencing, Avoidance and Numbing, and Physiological Hyperarousal) were computed in the same fashion, to permit a more fine-grained assessment. PTSD diagnosis (yes/no) also was derived from the CAPS, using the 1 (frequency)/2 (intensity) criterion as recommended by Blanchard

et al. (1996a,b). Probes were added to determine whether each PTSD symptom was attributable to pain (e.g., if a patient reported difficulty sleeping, the clinician assessed whether this symptom was due to pain and, if so, the symptom was not scored on the CAPS). The CAPS was administered by trained doctoral students. All interviews were videotaped and 30% (n = 55) were randomly selected and reviewed by an independent clinician to establish diagnostic reliability. Interrater agreement for diagnosis of PTSD was excellent (kappa = 0.86). As reviewed by Weathers, Keane, & Davidson (2001), the CAPS possesses strong reliability. Of particular

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importance, the CAPS is sensitive to the detection of PTSD in individuals following an MVA (Blanchard & Hickling, 2004). Additionally, the Impact of Event Scale–Revised (IES-R; Weiss & Marmar, 1997) was administered as a self-report measure of PTSD. The IES-R is a 22item scale that is rated on a 0 to 4 scale regarding how distressing each item has been during the past week. Scale scores are formed for three subscales, which reflect intrusion, avoidance, and hyperarousal. J. G. Beck et al. (2008) confirmed the threefactor structure in a sample of 182 MVA survivors and provided support for concurrent and discriminative validity of the IES-R. Internal consistency was good in the current sample (Intrusion: alpha = .92, Avoidance: alpha = .88, Hyperarousal: alpha = .86). Test-retest reliability, collected across a 6-month interval, ranges from .89 to .94 (Weiss & Marmar, 1997). Other PTSD measures. The MVA Interview (Blanchard & Hickling, 2004) was administered, which includes questions about emotional responses to the accident (feelings of fear, helplessness, danger, and perceptions that you might die) to determine whether the MVA qualified as a trauma within DSM-IV's definition. Each of these responses to the MVA was rated on a 0–100 Likerttype scale (0 = not at all to 100 = extreme), with a score of 50 or higher on ratings of fear, helplessness, or horror indicating that the MVA was experienced as traumatic. Assessment of anxiety and depression. Anxiety and depression were evaluated using both clinician and self-report measures. The Anxiety Disorders Interview Schedule for DSM-IV (ADIS-IV) was used as the clinician measure. As illustrated by Brown, DiNardo, Lehman, & Campbell (2001), the ADIS-IV has good psychometric properties and is widely used as a diagnostic tool. As with the CAPS, 30% (n = 55) of interviews were randomly selected and rated by an independent interviewer. Agreement between diagnosticians was good for social phobia (k = .88), generalized anxiety disorder (k = .96), specific phobia (k = .80), obsessive-compulsive disorder (k = .79), and major depressive disorder (k = .74).1 Two variables were computed from the ADIS-IV: (a) number of additional anxiety disorders and (b) number of depressive disorders. Two self-report measures also were used. The Beck Anxiety Inventory (BAI; A. T. Beck, Epstein, Brown, & Steer, 1988) was used to assess anxiety. The BAI is a 21-item self-report inventory of

1 Other diagnoses were not represented at a high enough frequency to compute kappa.

common anxiety symptoms that was developed to minimize overlap with depression. Participants rate the extent to which they were bothered by each item during the past week on a 0–3 scale. The inventory has been shown to be reliable in a sample of psychiatric outpatients (A. T. Beck et al., 1988). Internal consistency in the current sample was good (alpha = .94). Convergent validity of the BAI and other measures of anxiety has been noted (A. T. Beck et al., 1988; deBeurs, Wilson, Chambless, Goldstein, & Feske, 1997). The Beck Depression Inventory–II (BDI-II; A. T. Beck, Steer, & Brown, 1996) was used to assess depression. The 21 items of this scale are rated on a 0–3 scale to evaluate current depressive symptoms. One-week test-retest reliability was .93 among outpatients (A.T. Beck et al., 1996), and the scale is highly reliable with an alpha coefficient of .95 for the current sample. The BDI-II is correlated highly with other measures of depression (Steer & Clark, 1997), supporting its construct validity. Assessment of physical functioning and pain severity. Measures of physical function and pain severity were included for those individuals who reported pain complaints to assess whether treatment of PTSD would influence these dimensions. The Oswestry Disability Index (ODI; Fairbank, Couper, Davies, & O'Brien, 1980) was used to assess functioning. The ODI involves 10 questions that assess the ability to perform routine actions (e.g., lifting, walking). Each question has 6 response options, with higher values representing greater disability. The 10 responses are summed and expressed as a percentage of the total score. Testretest reliability has been reported at .99 (Fairbank et al., 1980), and internal consistency in the current sample was good (alpha = .90). The Pain Severity subscale of the Multidimensional Pain Inventory (PS-MPI; Kerns, Turk, & Rudy, 1985) also was included. This 3-item scale includes items that assess the severity of pain during the past week, as well as the perceived suffering from pain. Items are rated on a 0–6 Likert-type scale. Test-retest stability is reported to be .82 and internal consistency is acceptable, both in more typical pain patients (Kerns et al., 1985) and in the current sample (alpha = .85). The PS-MPI has been validated by itself as well as in concert with other subscales of the MPI (e.g., Turk & Rudy, 1988). In this report, standardized (t) scores are reported, to be consistent with related literature.

assessment of patient satisfaction (gcbt condition only) To examine patients' satisfaction with treatment, the Client Satisfaction Questionnaire (CSQ; Larsen,

group cbt for ptsd Attkisson, Hargreaves, & Nguyen, 1979) was administered during the last session of GCBT. This 8-item measure has been shown to be reliable in a sample of outpatients (Larsen et al., 1979) and performed similarly in the current sample (alpha = .80). Participants rate their satisfaction with treatment on a 4-point Likert-type scale, with higher scores indicating greater satisfaction.

assessment of treatment integrity (gcbt condition only) In order to evaluate treatment integrity, a measure of protocol adherence and therapist competence was developed. To assess adherence, a checklist was constructed for each session, containing a list of specific interventions that should be included, as well as a list of nonspecific techniques (e.g., encourages supportive atmosphere within the group), following the guidelines set forth by Waltz, Addis, Koerner, & Jacobson (1993). Therapist competence was rated using a 0–100 scale, where 0 indicated “not competent” and 100 indicated “extremely competent.” Each treatment session was videotaped and 59% (n = 41) were reviewed by an independent professional who was familiar with GCBT. treatment conditions GCBT. GCBT was based on Blanchard and Hickling's individual CBT, with several modifications. To accommodate the group format, treatment was extended to 14 weekly sessions, each lasting 2 hours. To standardize treatment, a detailed manual was developed. Exposure played a central role in GCBT, although this intervention was modified to suit the group environment. Specifically, imaginal exposure was assigned as homework and exposure to the target trauma (the MVA) was conducted in writing. Considerable time was spent reviewing exposure-based homework within each session. Emphasis was placed on teaching the principles of extinction to facilitate exposure during homework. Two therapists delivered GCBT, a choice that was guided by previous clinical experience treating PTSD in a group setting. GCBT included (a) psychoeducation (Session 1); (b) exposure, both in vivo and imaginal (Sessions 2– 14); (c) mindfulness meditation training and practice (Sessions 2–14) to ensure that anxiety generated by driving to the treatment session was manageable; (d) progressive muscle relaxation (Sessions 4–7) for stress management; (e) cognitive therapy interventions (Sessions 6–8); (f) application of cognitive interventions and assertion training to address anger (Sessions 9 and 10); (g) behavioral activation to address depression and social isolation

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(Sessions 11 and 12); and (h) relapse prevention training (Sessions 13 and 14). Specific details about this intervention can be found in J. G. Beck & Coffey (2005). GCBT was administered by three trained therapists who each had substantial clinical experience with trauma survivors. The first author served as a therapist for each group, with the other two professionals alternating in the role of co-therapist and adherence/competence rater. MCC. Individuals in the MCC group were contacted by telephone by the project coordinator once every 4 weeks during the span of 14 weeks. During these calls, a structured script was used to assess PTSD symptomatology as well as suicidality. Minimal support was provided but no active intervention was administered.

procedure All procedures were in compliance with the University's Institutional Review Board. When potential participants contacted the project, all procedures were explained and an initial evaluation (pretreatment: PRE) was scheduled. During this appointment, the CAPS, ADIS, and the MVA interview were administered. The remainder of the outcome measures were completed at home. Individuals who satisfied all inclusion criteria were offered admission to the study. Groups of four to seven individuals were formed as participants became eligible; a given group then was randomly assigned to either GCBT or MCC conditions. 2 Individuals in the GCBT condition (only) completed weekly records of medication use. No patient in this condition reported a change in psychotropic medication during treatment. Pain medications were permitted to vary, in keeping with medical management of chronic pain conditions. Four weeks after the completion of the assigned condition, participants were reassessed using each of the outcome measures (posttreatment assessment: POST). MCC participants then were offered GCBT. For GCBT participants, a follow-up (FU) assessment was conducted 3 months after POST. Interviews for the POST and FU assessments were administered by an individual who had not conducted the pre-treatment assessment and was unaware of patients' treatment status and their time of assessment (POST versus FU). Individuals were paid $25 per assessment for completion of POST and FU assessments to facilitate participation. 2 Randomization was done at the level of the group to avoid excessively long waits for treatment.

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Results attrition Of the 44 participants who were randomly assigned (26 to GCBT, 18 to MCC), 11 (25%) dropped out of the study prior to the POST assessment point. Seven individuals dropped out during GCBT (26.9%), two individuals completed GCBT but refused to complete the POST assessment (7.7%), and two dropped from the MCC condition (11%). The difference in rates of dropouts between GCBT and MCC was not statistically significant, χ2(1) = 3.31, p = .08.3 Comparison of completers with dropouts indicated no significant differences on any outcome measure at pretreatment, age, gender, race, or educational level (all p's N.05). Thus, 17 individuals completed GCBT and the POST assessment and 16 completed MCC and the POST assessment. Two individuals who completed GCBT failed to complete the FU assessment, resulting in n = 15 for these analyses. treatment adherence and competence Examination of the adherence data indicated that 98% of both specific and nonspecific interventions that were included in the manual were included in actual group treatment sessions. Competence was rated as excellent (M = 98.6, SD = 7.8). comparison of gcbt versus mcc In designing this analytic approach, a unique feature deserves explanation. Within the GCBT condition, patients were clustered into treatment groups, a situation that did not exist in the MCC condition. With input from D. Hedeker (personal communication, September, 2001), we designed our analytic strategy to accommodate this feature. Recognizing that there is concern about nonindependence of data derived from GCBT, we examined the intraclass correlation (ICC). In the event that the ICC was not substantial (≤ .1), we were reassured that nonindependence of the data was not a large concern. In the event that the ICC was substantial (N.1), we removed the variance that was attributable to group membership within the GCBT condition only. The residuals for these variables then were used in the examination of GCBT versus MCC. Examination of ICC values indicated that

3

Of the seven individuals who dropped out of GCBT, six provided reasons, which included two individuals who had to return to work and no longer had time for participation, a disabled patient who no longer had a ride to treatment, one individual who was looking for mental health services that focused on issues other than PTSD, and two individuals who did not attend at least 75% of the GCBT sessions.

this latter analysis was needed only for the CAPS Reexperiencing subscale and the ODI. To examine outcome among individuals who attended at least 75% of GCBT sessions in comparison with MCC, a series of Group (GCBT, MCC) × Time (PRE, POST) analyses of variance was conducted. Owing to the fact that Time was a repeated measure, the multivariate analysis of variance algorithm was used (Vasey & Thayer, 1987). As recommended by Greenwald, Gonzalez, Harris, & Gutherie (1996), we report exact p values for these tests. Significant effects were followed via Tukey's procedure, using comparison-specific error terms for effects that involved the repeated factor and p ≤ .05 as the criterion for statistical significance. Effect size was calculated using Hedge's unbiased g (Hedges, 1981) to be comparable with effect sizes calculated by the International Society for Traumatic Stress Studies treatment guidelines (Foa, Keane, & Friedman, 2000). Means and standard deviations for all dependent variables are reported in Table 1. Assessment of PTSD. For the CAPS variables, a significant Group × Time interaction was noted for the CAPS Total score, F(1, 31) = 5.71, p = .02, and the CAPS Avoidance subscale, F(1, 31) = 8.5, p = .007. For the CAPS Total score, Tukey's procedure indicated that, although both GCBT and MCC showed significant reductions from PRE to POST, the GCBT mean was significantly lower at POST relative to the MCC mean. For the CAPS Avoidance subscale, Tukey's procedure indicated that only the GCBT condition showed a significant reduction from PRE to POST. Comparison of group means at POST indicated that the GCBT condition was significantly lower than the MCC condition on this measure. Examination of the CAPS Reexperiencing score revealed a significant Group effect, F (1, 31) = 74.41, p = .0001, with the GCBT condition reporting lower scores overall, relative to the MCC condition. The CAPS Hyperarousal score revealed a significant Time effect, F(1, 31) = 15.58, p = .001, indicating that both groups showed a reduction from PRE to POST. Examination of the IES-R indicated a significant Group × Time interaction for the Intrusion subscale, F(1, 31) = 5.2, p = .03, the Avoidance subscale, F(1, 31) = 4.1, p = .05, and the Total score, F(1, 31) = 4.7, p = .03. For the Avoidance subscale and the Total score, Tukey's procedure indicated that, although both GCBT and MCC showed significant reductions from PRE to POST, the GCBT mean was significantly lower at POST relative to the MCC mean. For the Intrusion subscale, Tukey's procedure indicated that only the GCBT condition showed a significant reduction from PRE to

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group cbt for ptsd POST. Comparison of group means at POST indicated that the GCBT condition was significantly lower than the MCC condition on this measure. Analysis of the IES-R Hyperarousal subscale revealed a significant Time effect, F(1, 31) = 5.16, p = .03, indicating a reduction from PRE to POST. As well, a significant Group effect, F(1, 31) = 5.87, p = .02, was noted, indicating that the GCBT condition had lower scores overall. Assessment of anxiety and depression. Examination of the number of additional anxiety disorders indicated a significant Time effect, F(1, 31) = 9.99, p = .004, which revealed a significant reduction from PRE to POST. Examination of the BAI, the number of depressive disorders, and the BDI-II did not reveal any significant effects. Assessment of physical functioning and pain severity. Examination of the ODI revealed a significant Group effect, F(1, 31) = 88.24, p = .0001, which indicated that the GCBT patients reported less disability overall, relative to the MCC patients. Examination of the PS-MPI revealed a significant Time effect, F(1, 31) = 7.61, p = .01, which indicated that both groups showed a reduction in pain severity from PRE to POST. Diagnosis and end-state functioning. Computation of the percentage of patients who continued to meet criteria for PTSD at POST indicated that significantly fewer patients in the GCBT condition continued to have the disorder (11.7%), relative to the MCC condition (68.7%, χ2[1] = 11.21, p = .001). To determine high end-state functioning, we computed two indices. Reliable change (RC) represents a means of quantifying how much change has occurred over treatment. As discussed by Jacobson & Truax (1991), when functional and pretreatment distributions are overlapping, it is possible for a patient's posttreatment score to exceed the cutoff for clinical significance but not represent statistically reliable change. Thus, RC is considered a stringent end-state measure (Jacobson & Truax, 1991). As shown in Table 2, 8 (47.1%) participants in the GCBT condition and 6 (37.5%) in the MCC condition met criteria for RC on the IES-R Total, χ2(1) = 0.23, ns. On the CAPS Total score, 14 (82%) individuals in the GCBT condition and 8 (50%) in the MCC condition met criteria for RC, χ2(1) = 3.75, ns. Second, we examined high end-state functioning, using the definition provided by Bryant, Moulds, Gutherie, Dang, & Nixon (2003), specifically, scoring below 19 on the CAPS-Total score and below 10 on the BDI-II. As noted in Table 2, 5 (29.4%) individuals in the GCBT condition and 2 (12.5%) in the MCC condition met these criteria at POST, χ2(1) = 1.14, ns.

Table 2 Summary statistics for percentage of patients meeting criteria for PTSD and scored in Reliable Change and High End State categorizations at POST and FU assessment points (number of participants shown in parentheses) Percentage meeting criteria for PTSD

Reliable change

High end state

IES-R Total

CAPS total

POST GCBT 11.7% (2/17) (n = 17) MCC 68.7% (11/16) (n = 16)

47.1% (8) 37.5% (6)

82% (14) 31.3% (5)

29.4% (5) 12.5% (2)

FU GCBT 6.7% (1/15) (n = 15)

53.3% 8)

93.3% (14)

40% (6)

Note. High end state = Scoring below 19 on the Clinician Administered PTSD Scale and below 10 on the Beck Depression Inventory–II. GCBT = Group Cognitive Behavioral Treatment; MCC = Minimal Contact Comparison; IES-R = Impact of Event Schedule, Revised.

Satisfaction with treatment. Examination of the CSQ indicated that members of the GCBT condition were satisfied with treatment (M = 29.6, SD = 2.48).

stability of change: comparison of post to fu To examine the stability of treatment gains, pairedsamples t-tests were used to compare scores at POST with scores at FU for the GCBT condition. Significant reductions between POST and FU were noted for the CAPS Total, t(14)= 2.78, p = .02, CAPS Avoidance and Numbing subscale, t(14) = 2.39, p = .03, and CAPS Hyperarousal subscale, t(14) = 2.17, p = .05. No significant differences were noted on any of the self-report measures. As can be seen in Table 1, gains that were reported at POST were maintained at FU.

Discussion This study compared GCBT with a minimal contact comparison condition with respect to efficacy for the treatment of PTSD in the aftermath of a serious MVA. At posttreatment, a significant reduction was noted in PTSD symptoms among patients in the GCBT condition, whether assessed by clinician interview or self-report. Following treatment, 88.3% of patients receiving GCBT did not satisfy criteria for PTSD, relative to 31.3% of the comparison group. Stability of gains was noted at 3-month follow-up. Examination of anxiety, depression, and pain measures did not show a unique advantage of GCBT. Attrition from this treatment was comparable with other treatment

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studies of individual CBT (e.g., 27% GCBT versus 27% individual CBT [Blanchard et al., 2003], 26.8% Cognitive-Processing Therapy, 27.3% Prolonged Exposure [Resick, Nishith, Weaver, Astin, & Feuer, 2002]). Importantly, these reductions in PTSD appear to be comparable to those obtained with individual CBT. For example, Blanchard et al. (2003) reported that of those individuals with PTSD, 76% remitted following individual CBT. Likewise, Maercker et al. (2006) reported that 75% of patients originally diagnosed with PTSD did not meet diagnostic criteria after individual CBT. Neither of these reports included RC or high end-state computations, so comparison across trials on these metrics is not possible. The comparable results with respect to remission of PTSD that were obtained in the current study support speculation offered by authors such as Resick, Hickling, and Foy that development of a group CBT intervention requires adaptation of specific techniques and attention to the group process elements of treatment. With these modifications, outcomes were comparable with the individualized format of this treatment. Ideally, a direct comparison of individual versus group CBT is necessary to determine areas of similarity and difference in efficacy. Although the outcome with respect to PTSD appears similar for group and individual treatment, differences appear when considering generalized effects for anxiety and depression. As noted, GCBT did not appear to reduce comorbid anxiety and depressive disorders, unlike individual CBT (Blanchard et al., 2003; Maercker et al., 2006). Because GCBT involved a standardized protocol, group members received two standardized modules addressing depression and no specific attention to general anxiety complaints. For individuals with depressive and anxiety disorders, this would not be a sufficient amount of intervention. Thus, the current study indicates that one arena where GCBT could use further development is in the incorporation of methods to improve generalizability to comorbid conditions. A related issue involves the impact of chronic pain in the treatment of MVA-related PTSD. Although some authors note that the presence of pain is associated with poor treatment response to GCBT (Taylor et al., 2001), it is notable that this particular finding occurred in the context of treatment that was not adapted for use in a group setting and had lower overall efficacy. In the current study, 80% of the sample reported pain complaints stemming from injuries sustained during the MVA; this did not appear to adversely influence observed outcomes. Much as reported by Shipherd, Beck,

Hamblen, Lackner, & Freeman (2003) for individualized CBT, GCBT appears appropriate for the patient who has comorbid PTSD and chronic pain in the aftermath of a serious MVA. Future research might examine if pain-related functioning changes during the treatment of PTSD in these patients. One issue that deserves comment is the modifications that were made to exposure therapy to accommodate group treatment. Patients were taught the principles of extinction during group sessions, with an emphasis on conducting exposure during daily homework. A considerable amount of each session was spent reviewing homework as a way of insuring that they understood the principles while also reinforcing patients' practice efforts. Clearly, this approach puts considerably greater control for conducting exposure in the patient's hands. Patients varied widely with respect to their initial understanding of exposure and their willingness to begin their first exposure exercise. One benefit of the group treatment environment was the ready source of social support for exposure homework. Patients who initially were reluctant to begin exposure often received encouragement from other group members, which seemed to be a powerful motivator. The GCBT protocol used a gradual exposure model, asking patients to start with an item that was anxiety-provoking but manageable and to work up their hierarchy each successive week. This model was based on experimental data that suggests that spaced exposure, using a changing intertrial interval, combined with varied stimulus exposure training produces the most generalization and least return of fear following treatment (e.g., Rowe & Craske, 1998a, b). Although prolonged exposure in session is used more commonly in the treatment of PTSD (e.g., Rothbaum, Meadows, Resick, & Foy, 2000), data from this trial suggest that alternative approaches to exposure can be effective as well. Like most empirical studies, the current report has some limitations. First, the sample size was relatively small and did not allow examination of the effects of specific group dynamics on outcome. Although the analytic strategy was crafted to ensure that nonindependence owing to group membership was not a source of error, this did not allow consideration of group-specific interpersonal processes that may have influenced outcome. Future studies of GCBT for PTSD may wish to examine whether group process influences outcome. Second, GCBT was conducted by its developers. Although it is not unusual for treatment developers to serve as therapists during this stage of treatment development (e.g., Rounsaville, Carroll, & Onken, 2001), it is possible that future trials of GCBT may obtain

group cbt for ptsd different outcomes, given the possibility of investigator effects in the current trial. Third, the followup interval was short. Although stability of effects was noted 3 months after treatment, a longer follow-up interval should be used in future studies. As well, given limitations imposed by the design and methodology of the study, intent-to-treat analyses were not included. Lastly, it is difficult to ascertain if these results will generalize to survivors of different kinds of traumatic events. Although the sample used in this study reported similar levels of PTSD severity as seen in other studies involving MVA survivors (e.g., Blanchard et al., 2003; Maercker et al., 2003), their symptomatology was less pronounced than survivors of other types of traumas (e.g., sexual assault, Resick et al., 2002; combat, Monson et al., 2006) As recognized by Keane, Marshall, & Taft (2006), the psychological literature does not suggest differential effectiveness of exposure-based interventions across different trauma populations but examining the effectiveness of GCBT in different trauma groups seems prudent, particularly given differences in severity of PTSD. Notably, many of the limitations noted in this study are intrinsic to initial pilot studies and can be readily addressed in subsequent trials. In sum, these results suggest that group CBT can be effective in the treatment of PTSD in the aftermath of a serious MVA. Rates of remission of PTSD approximated those found in individual CBT, as did rates of attrition. Although preliminary, these results suggest that additional research with this treatment modality is warranted, particularly studies involving trauma populations that have traditionally been underserved (e.g., domestic violence survivors) or where there is a large influx of new cases (e.g., combat veterans). The encouraging and positive results of this study suggest the need for continued study of GCBT. References American Psychiatric Association. (2000). Diagnostic and statistical manual of mental disorders, 4th ed., text revision Washington, DC: Author. Beck, A. T., Epstein, N., Brown, G., & Steer, R. A. (1988). An inventory for measuring clinical anxiety: Psychometric properties. Journal of Consulting and Clinical Psychology, 56, 893–897. Beck, A. T., Steer, R. A., & Brown, G. K. (1996). Manual for the Beck Depression Inventory–II. San Antonio, TX: Psychological Corporation. Beck, J. G., & Coffey, S. F. (2005). Group cognitive behavioral treatment of PTSD: Treatment of motor vehicle accident survivors. Cognitive and Behavioral Practice, 12, 267–277. Beck, J. G., Grant, D. G., Read, J. P., Clapp, J. D., Coffey, S. F., Miller, L. M., et al. (2008). The Impact of Event ScaleRevised: Psychometric properties in a sample of motor

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