Manualized Therapy for PTSD: Flexing the Structure of Cognitive Processing Therapy

A number of psychological interventions have demonstrated substantial empirical support in the remediation of posttraumatic stress disorder (PTSD) over the course of the last two decades, including prolonged exposure (PE), cognitive processing therapy (CPT), and eye movement desensitization reprocessing (EMDR; Institute of Medicine [IOM], 2008). As a result of this growing accumulation of evidence, the scientific community has endorsed specific therapies as “empirically supported” and numerous national organizations designated best practice guidelines (BPGs; e.g., IOM, 2008). Since the establishment of BPGs, efforts toward dissemination of these interventions to community care have significantly increased (Karlin et al., 2010). Despite these historically herculean efforts to disseminate the fruits of interventions developed in academic settings and tested in randomized controlled trials (RCTs), barriers to implementing evidence-based practice (EBP) into clinical care remain. The extant literature is replete with numerous explanations for these historical difficulties in the successful dissemination and implementation of EBPs (Freiheit, Vye, Swan, & Cady, 2004; Kazdin, 2008). Objections to the integration of EBPs may stem from general dissonance around the application of the seemingly rigid “cookbook approach” of manualized therapies to the perceived complexity of distress observed in many clients seeking services in community care settings. The debate over EBP guidelines began almost immediately following the APA Task Force on Promotion and Dissemination of Psychological Procedures’ (1995) recommendations. A host of criticism for the implausibility of the APA’s recommended use of empirically supported treatments in clinical practice resounded through both clinical and academic circles resulting in a special issue of Journal of Consulting and Clinical Psychology (1998). Some of the strongest criticisms against the proclaimed empirical support of the cited interventions included the lack of flexibility of treatment manuals in RCTs (Beutler & Howard, 1998), the focus on outcome rather than processes of therapy (Barlow, 1996), the fixed number of sessions contained in protocols (Jacobsen & Christensen, 1996), the use of highly trained, expert clinicians to administer the intervention (Chambless & Hollon, 1998), the focus on diagnostic outcome rather than client level of functioning, and lack of overall ecological validity (Persons & Silberschatz, 1998). More recently, participant attrition and non-response rates reported in RCTs have also been cited as evidence that no given psychotherapy has generated sufficient empirical support to be labeled as an EBP for the treatment of PTSD (Schottenbauer, Glass, Arnkoff, Tendick, & Gray, 2008). RCTs for manualized PTSD treatments indicate that approximately one-third of the participants remain refractory to treatment and approximately one-quarter of the samples drop out prematurely (Bradley, Greene, Russ, Dultra, & Westen, 2005; Schottenbauer, Glass, Arnkoff, Tendick, & Gray, 2008). Although continued empirical support and significant advances have accumulated since the beginning of this debate in the 1990s, the integration of EBPs into community care remains challenging at best (Kazdin, 2008). Specifically, with respect to utilizing EBPs in the treatment of PTSD, Cook, Schnurr, and Foa (2004) suggest that researchers actively attend to clinicians’ concerns and challenges regarding the use of manual-based treatment. The current study sought to evaluate modifications to an existing evidence-based protocol (CPT) in an effort to more closely mimic practice by community clinicians and empirically address perceived barriers to implementation of evidence-based practice. CPT has accumulated significant empirical support and has been identified as an EBP for the treatment of PTSD (IOM, 2008). To date, four RCTs have been published demonstrating the efficacy of the intervention across trauma samples, including female survivors of sexual and physical assault (Resick, Nishith, Weaver, Astin, & Feuer, 2002; Resick, Galovski, et al., 2008), survivors of childhood abuse (Chard, 2005), and veterans (Monson et al., 2006). Consistent with the larger PTSD outcome literature, in which approximately 20% to 50% of the sample remains PTSD-positive after a course of psychotherapy (Bradley et al., 2005; Schottenbauer et al., 2008), results from the CPT trials also leave room for improvement. In comparing the full, 12-session CPT protocol to PE, Resick et al. (2002) reported that 19.5% of the CPT group retained their PTSD diagnosis after completing the 12-session protocol. Similarly, in their dismantling study, Resick, Galovski, and colleagues (2008) reported that 29.6% of the CPT completer group was PTSD-positive at post-treatment. Further inspection of the outcome data in these two CPT trials (Resick et al., 2002; Resick et al., 2008) suggests that it may not be entirely accurate to conceptualize these PTSD positive treatment completers as “refractory” or “non-responders”, despite their PTSD positive status at the end of therapy. It may be more accurate to describe these individuals as “partial responders”, because PTSD and depressive severity scores decreased significantly on average from pre-treatment to post-treatment in this subset of completers (Galovski & Blain, 2008). The downward trends in symptomatology suggest that these individuals may be slower to respond and simply had not yet reached optimal levels of improvement by the conclusion of the 12-session protocol. Chard (2005) uniformly lengthened the 12-session protocol to a 17-session protocol using a combined individual and group modality. Results from this trial indicate that only 7% of the CPT completers met PTSD criteria at post-treatment assessment. However, it is unknown whether these lower rates of PTSD caseness at treatment’s end can be attributed to the longer course of therapy (as PTSD status was not assessed at session 12), to the combination of group and individual care, or to other possible sources of variance. The question remains whether individuals who retain their PTSD diagnosis following a full course of CPT continue to improve or whether additional therapy will have diminished returns. The current study sought to empirically evaluate the benefit of continued therapy until a specific outcome criterion was met. There is some evidence to suggest that a portion of CPT completers demonstrate a pattern of response that is consistent with the observed phenomenon of “sudden gains” or significant improvements within a full course of therapy. Kelly, Rizvi, Monson, and Resick (2009) investigated sudden gains (defined as rapid and stable improvement) in a course of CPT for survivors of interpersonal violence suffering from PTSD. Results indicated that sudden gains occurred in approximately 39% of participants. Sudden gains made during the course of therapy predicted greater overall symptom reductions at the conclusion of therapy, but were not related to the amount of symptom reduction at the 6-month follow-up assessment, suggesting that sudden gains can occur in CPT, but that those individuals who did not experience a sudden gain “caught up” over time. However, by definition, a sudden gain reflects significant change between two data points (in this case, treatment sessions). This within-protocol change was previously used to predict the overall degree of change after the participant received the full dose of the therapy. While these findings suggest that the phenomenon of rapid and efficient response to treatment within a standard course of CPT are associated with overall improvement at treatment termination, examination of a flexible termination point defined by pre-determined criterion of good end-state functioning has not been examined. There is little information regarding the maintenance of treatment gains in the long-term for those individuals who indicate a rapid and efficient response to treatment during the administration of the protocol. Finally, there is virtually no information on predictors of early and efficient treatment response versus a longer course of therapy. This study sought to assess whether a trauma survivor suffering from PTSD can achieve good end-state criteria prior to the full dose of therapy and continue to maintain these gains at the long-term follow-up. Possible predictors of efficiency of response were also explored.