The current study found that it was possible to observe, record, and reliably code the number and percentage of assimilated, overaccommodated, and accommodated statements that rape survivors produced in their impact statements at the beginning and end of a course of CPT. Although the methodology was not identical, the findings of the current study are compatible with those of a prior study that coded therapy material (Ehlers et al., 1998
). Ehlers and colleagues found that of 20 women who had been sexually assaulted, those showing the fewest gains from exposure-based therapy had a variety of inaccurate thoughts pertaining to mental defeat, alienation, and a sense of permanent, negative life change. These authors proposed that such cognitions might be successfully modified using cognitive restructuring and exposure-based treatment.
In support of the impact of cognitive–behavioral treatments, the current study found that a course of CPT was associated with altered thoughts. As hypothesized, there were significant decreases in the number and percentage of overaccommodated and assimilated clauses from the start to the end of therapy. In addition, as predicted, there was an increase in the number and percentage of accommodated clauses. For instance, one client's pretreatment, assimilated statement was that she felt “tons of guilt”; however, her end-of-treatment, accommodated statement was that “it wasn't my fault, it was his.” Additionally, her pretreatment, overaccommodated belief was that she needed “to be in control at all times” or “I can’t breathe.” In contrast, at the end of therapy she stated, “I have learned to trust my own instincts.” This shift revealed a more accommodated belief. These results are consistent with studies that have found that a course of CPT reduces the severity of cognitive distortions as measured by quantitative assessment instruments (Owens et al., 2001
; Resick et al., 2002
Partial support was found for the prediction that higher rates of overaccommodation and assimilation would be related to greater symptomatology, and that more accommodation would accompany lower symptom levels. At the beginning of treatment, only the percentage of accommodated clauses was significantly and negatively correlated with self-reported PTSD symptoms. It is possible that there was no correlation between PTSD and overaccommodation at pretreatment because of ceiling effects. At the end of treatment, however, the number and percentage of overaccommodated clauses was significantly and positively related to PTSD symptoms (i.e., both self-reported and clinician-rated). Additionally, the percentage of accommodated clauses was significantly and negatively correlated with self-reported and clinician-rated PTSD symptoms. These findings were consistent with prior studies showing significant relationships between distorted cognitions and symptoms.
Finally, we predicted that reductions in assimilation and overaccommodation and increases in accommodation would be related to decreases in symptoms over the course of treatment. Such a relationship was found between changes in accommodation and overaccommodation and self-reported PTSD scores. This finding supports the idea that trauma survivors who made stronger, positive, cognitive changes also achieved greater levels of symptom relief.
Although many of the study hypotheses were supported, a limitation was that it was often clear to the coders whether the impact statement was written at the beginning or the end of treatment, even after removing identifying information. When coding the content of the statements, it was not possible to disguise a stated or implied change in beliefs from pre- to posttreatment (e.g. “Before therapy, I used to believe this, but now I think. . . ”).
Another finding that needs further explanation is the lack of significant relationships between assimilation and PTSD. At the end of treatment, we found that none of the 37 participants generated assimilated statements. One explanation for this finding is that CPT helped clients identify and challenge self-blaming or undoing thoughts. Prior research supports this interpretation by demonstrating that self-blaming, assimilated thoughts have been linked to PTSD (Kubany & Manke, 1995
) and that recovery from PTSD is associated with reductions in guilt cognitions and shame (Resick et al., 2002
). An alternative explanation for the lack of relationship between assimilation and PTSD is that even at the beginning of treatment, the base rate of assimilation was low (i.e., an average of only 2.5 statements). This result is probably due to reduced statistical power resulting from a low pretreatment rate of assimilated clauses as well as a lack of assimilated clauses at the conclusion of therapy.
A possible explanation for the low base rate of assimilated statements is that the impact statement instructions may not have sufficiently encouraged clients to explore their assimilated thoughts. This hypothesis must be considered, particularly given the strong association that has been found between PTSD and assimilated beliefs (e.g., denial, self-blame, undoing) in prior investigations (e.g., Frazier & Schauben, 1994
; Kaysen, 2003
; Kubany et al., 1996
; Kubany & Manke, 1995
; Owens et al., 2001
; Wenninger & Ehlers, 1998
). The instructions for the impact statement did not prompt clients to explore their beliefs about the cause of the rape; thus, there were likely fewer assimilated statements than there might have been with different instructions. In the latest version of the CPT manual (Resick, Monson, & Chard, 2007
), the impact statement assignment explicitly asks for the client's beliefs about the causes of the traumatic event as well as the implications for the person's life. Future research might be able to examine whether these new impact statements result in more assimilated statements.
Another potential issue is that the impact statement instructions may have suggested a frame of understanding, which in turn, biased the clients’ responses. Piaget (1987)
proposed that people engage in assimilation and accommodation as they form schemas, which are constructions of reality that arise as a result of how one processes environmental information. In the impact statement instructions, participants were asked to “consider the following topics while writing your answer: safety, trust, power/control, esteem, and intimacy.” It is possible that their responses were unduly influenced by the suggestion of specific themes, which in turn, increased the likelihood of producing particular types of statements.
More limitations include the lack of ethnic minority participants and the fact that PTSD did not remit in a portion of the clients. Because 84% of the participants were Caucasian and only 14% were African American, we were not able to conduct statistical analyses to examine potential differences in cognitions as a function of ethnicity; thus, it is not possible to generalize the findings of this study to ethnic minority groups. It is also noted that at pretreatment, everyone in the study met full criteria for PTSD; at the end of treatment, 22% met the criteria. We do not fully understand why some people respond to treatment whereas others do not. We hypothesize that perhaps some clients may not be as skilled in challenging their faulty cognitive assumptions, or they may be less flexible in their reasoning processes; however, this is an area that needs further exploration.
Study participants showed large reductions in PTSD across time as well as changes in cognitions; however, the causal explanation for these changes is somewhat ambiguous. It is possible that CPT helped clients to reappraise and contextualize their traumatic events, developing more balanced views about their assaults, and that these cognitive changes were related to reductions in PTSD. It could also be the case, however, that exposure to the traumatic event via therapy resulted in extinction of PTSD symptoms and that cognitive change was a byproduct of that process. It is also possible that a third factor, such as increased hope or self-efficacy, produced reductions in both distorted cognitions and symptom levels. Research utilizing longitudinal designs that can examine mediation with larger samples is needed to further explore these potential causal pathways. Additionally, future investigations might compare the impact statements of successful treatment clients with those of treatment nonresponders to analyze whether positive changes in cognitions occur in the absence of symptom reduction.
In summary, the current investigation provides support for the utility of cognitive–behavioral interventions in reducing inaccurate thoughts. Given the encouraging findings of this investigation, as well as those of other studies, we may tentatively conclude that CPT is related to reductions in trauma-related cognitive distortions. Future research replicating and extending these findings would be a welcome addition to the treatment literature. More in-depth qualitative analysis may also provide a complement to our understanding of cognitive processes in recovery from PTSD.