Th e terms cognitive therapy and cognitive behavioral therapy (CBT) are often used interchangeably. Although cognitive therapy refers specifi cally to the Beckian approach, CBT is broader and is used to designate a set of techniques in which the cognitive therapy approach is used along with behavioral strategies (Beck, 2005; Dobson &
Dozois, 2010).
Most empirical attention has been on cognitive therapy for major depressive disor- der, with more than 75 clinical trials published since 1977 (see Butler et al., 2006). Th e data indicate that cognitive therapy is comparable to antidepressant medication for the acute treatment of depression, with both treatments producing results superior to pla- cebo control conditions (see Hollon, Th ase, & Markowitz, 2002). Recent studies have also demonstrated that cognitive therapy and pharmacotherapy are equally eff ective for severe depression (DeRubeis et al., 2005; Hollon et al., 2005; DeRubeis, Gelfand, Tang,
& Simons, 1999). A particular benefi t of cognitive therapy relative to antidepressant medication is that fewer patients (i.e., approximately half ) relapse (Gloaguen, Cottraux, Cucherat, & Blackburn, 1998; but see Wampold, Minami, Baskin, & Tierney, 2002).
Th e prophylactic eff ect of cognitive therapy was also recently demonstrated for severe
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depression (Hollon et al., 2005). However, Dimidjian et al. (2006) recently found that behavioral activation produced prophylactic eff ects similar to cognitive therapy.
Butler et al. (2006) reviewed meta-analyses of treatment outcome for cognitive behavioral therapies for a number of psychological disorders. A total of 15 methodologi- cally rigorous meta-analyses were identifi ed between 1967 to 2004, which incorporated 9,995 research participants in 332 studies. Large eff ect sizes were obtained for unipolar depression, generalized anxiety disorder, panic disorder, social anxiety, and childhood internalizing problems. Moderate eff ect sizes were found for couple distress, anger, childhood somatoform disorders, and chronic pain. Small eff ect sizes were obtained for sexual off enders. Cognitive behavioral therapy also showed promising results as an adjunct to mediation for schizophrenia (Beck et al., 2008; but see Lynch, Law, &
McKenna, 2010).
Epp and Dobson (2010) recently reviewed the treatment outcome literature for cog- nitive behavioral therapy (including Beck’s cognitive therapy and other cognitive and behavioral approaches) and summarized the meta-analytic data according to absolute effi cacy (the extent to which cognitive behavioral therapy exhibits favorable outcome to no treatment, a wait list, or treatment as usual), effi cacy relative to pharmacotherapy, and effi cacy compared to other forms of psychotherapy (see Table 2.3; also see Dobson
& Dobson, 2009). As demonstrated by Epp and Dobson (2010) and D. Dobson and Dobson (2009), cognitive therapy has garnered considerable supportive evidence. For some disorders (e.g., some anxiety disorders, bulimia nervosa), the evidence is strong enough to suggest that cognitive behavioral therapy should be considered the treatment of choice. Since publication of these reviews, a meta-analysis focusing on schizophrenia, severe depression, and bipolar disorder has not been as positive. Lynch et al. (2010) sug- gested that cognitive behavioral therapy is no more eff ective than nonspecifi c interven- tions for the treatment of schizophrenia and does not appear to reduce the risk of relapse (but see Kingdon, 2010).
Treatment Mechanisms/Processes
Beck’s approach seeks to have a positive impact on emotional well-being and behavior by restructuring idiosyncratic belief systems that have become distorted or out of sync with the evidence. Although researchers disagree on the specifi c change processes that take place over the course of successful cognitive therapy, it is generally agreed that they are cognitive in nature (for reviews, see DeRubeis et al., 2010; Garratt et al., 2007;
Whisman, 1993).
A number of studies have examined changes in cognitive indices over the course of cognitive therapy. For example, research has demonstrated that CT for depression is as- sociated with signifi cant reductions in dysfunctional attitudes, attributional style, hopeless- ness, and cognitive bias (e.g., Beevers & Miller, 2005; DeRubeis et al. 1990; Jarrett, Vittengl, Doyle, & Clark, 2007; Oei & Sullivan, 1999; Rector, Bagby, Segal, Joff e, & Levitt, 2000;
Westra, Dozois, & Boardman, 2002; Whisman, Miller, Norman, & Keitner, 1991). In
Table 2.3 Summary of Effi cacy Findings by Disorder or Problem
Disorder Treatment
Absolute Effi cacy
Effi cacy Relative to Medications
Effi cacy Relative to Other Psychotherapies Unipolar
depression
CBT + + ∼
Bipolar disorder* CBT + =
Specifi c phobia Exposure and cognitive restructuring
++ + +
Social phobia Exposure and cognitive restructuring
++ ∼ ∼
Obsessive- compulsive disorder
Exposure and response prevention and cognitive restructuring
+ +
Panic disorder Exposure and cognitive restructuring
++ ∼ +
Chronic post-traumatic stress disorder
Exposure and cognitive techniques
+ =
Generalized anxiety disorder
CBT + + +
Bulimia nervosa CBT + + +
Binge-eating disorder
CBT + =
Anorexia nervosa CBT + + =
Schizophrenia* CBT + +
Marital distress CBT + ∼
Anger & violent off ending
CBT +
Sexual off ending CBT + −** +
Chronic pain CBT + ∼
Borderline personality disorder
CBT + ∼
(continued )
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their review, Garratt et al. (2007) concluded that the research literature is generally consistent with the notion that cognitive therapy yields cognitive change that, in turn, predicts reductions in depressive symptomatology. Tang and DeRubeis (1999) also demonstrated that substantial reductions in depressive symptoms (“sudden gains”) were preceded by signifi cant cognitive shifts, such as when patients modifi ed a maladaptive core belief. Th ese fi ndings have been replicated in subsequent studies (see DeRubeis et al., 2010, for review).
Research also suggests that shifts in threat-related cognitions and processing are associated with, and in some instances precede, improvement in cognitive behavioral therapy for anxiety. For example, a reduction in attentional biases toward threat have been found following cognitive behavioral therapy for generalized anxiety disorder (Mathews, Mogg, Kentish, & Eysenck, 1995), social anxiety disorder (Mattia, Heimberg,
& Hope, 1993), and specifi c phobia (Lavy, van den Hout, & Arntz, 1993). Some studies have also demonstrated that changes in anxious cognitions predict symptom changes in cognitive behavioral therapy for panic disorder and social phobia (e.g., Hofmann et al., 2007), although not all evidence pertaining to cognitive mediation has been supportive (for reviews, see Arch & Craske, 2008 and Hofmann, 2008a). Longmore and Worrell (2007), for instance, argue that component analyses have often failed to support the idea that cognitive techniques add to treatment outcome. As Hoff man (2008a) points out, the failure to fi nd that cognitive restructuring improves outcome over and above exposure-based strategies does not, however, preclude the possibility that these outcomes are mediated cognitively.
Substance-use disorders
CBT + =
Somatoform disorders
CBT + + +
Sleep diffi culties CBT + + +
Note: A blank space indicates insuffi cient or no evidence; − indicates negative evidence; + indicates positive evidence; = indicates approximate equivalence; ++ indicates treatment of choice, ∼ indicates equivocal evidence, “CBT” indicates effi cacy of specifi c components unknown; * indicates that CBT is typically used as an adjunct to medication in these disorders; ** indicates effi cacy relative to physical treatments (i.e., surgical castration and hormonal treatments).
Source: From “Th e Evidence Base for Cognitive-Behavioral Th erapy,” by A. M. Epp and K. S. Dobson, 2010. In K. S. Dobson (Ed.), Handbook of Cognitive-Behavioral Th erapies (3rd ed., pp. 39–73). New York, NY: Guilford Press. Reprinted with permission.
Table 2.3 (continued )
Disorder Treatment
Absolute Effi cacy
Effi cacy Relative to Medications
Effi cacy Relative to Other Psychotherapies
Most research that assesses cognitive mediation of symptom reduction has focused on the relative effi cacy of cognitive therapy and antidepressant medication for de- pression. Some research has demonstrated that cognitive interventions are associated with greater reductions in dysfunctional attitudes related to need for social approval, hopelessness cognitions, low self-concept, and cognitive bias (e.g., Rush, Beck, Kovacs, Weissenburger, & Hollon, 1982; Whisman et al., 1991). However, these fi ndings have also not been uniformly replicated (e.g., Simons, Garfi eld & Murphy, 1984; Moore &
Blackburn, 1996). Indeed, shifts in cognitive content and processes are also associated with successful pharmacotherapy (e.g., Dozois et al., 2009).
As DeRubeis, Siegle, and Hollon (2008) have argued, however, antidepressants
“seem to be symptom-suppressive rather than curative” (p. 789). For example, cognitive therapy and antidepressant medication may be equivalent in their modifi cation of more surface-level cognitions (e.g., negative automatic thoughts and dysfunctional attitudes), but may diff er in their ability to modify “deeper” cognitive structures. Segal, Gemar, and Williams (1999) administered the Dysfunctional Attitude Scale (DAS) to patients who had successfully completed either a trial of cognitive therapy or pharmacotherapy.
Th e DAS was administered before and after a negative mood induction procedure, in which participants were to think about a time in their lives when they felt sad. While in a neutral mood state, there were no signifi cant between-group diff erences on the DAS.
Following the mood induction, however, those individuals successfully treated with antidepressants exhibited an increase in dysfunctional attitudes, an eff ect that was not evident in those treated with cognitive therapy (also see Segal & Gemar, 1997). Segal et al. (2006) further documented that this mood-reactivity predicted relapse 18 months later. Such fi ndings indicate that cognitive therapy may diff erentially alter cognitive pat- terns associated with relapse.
More recently, Dozois et al. (2009) compared the combination of cognitive therapy and pharmacotherapy (CT+PT) to pharmacotherapy (PT) alone on depressive symp- toms, surface-level cognitions (e.g., negative automatic thoughts) and the organization of self-representation (e.g., cognitive structures). Both groups showed signifi cant and equivalent reductions in depressive symptoms, automatic thoughts, and dysfunctional attitudes. Individuals treated with CT+PT, however, demonstrated signifi cantly greater cognitive organization (interconnectedness of adjective content) of positive interper- sonal content and less well-connected negative interpersonal content than did individu- als treated with medication alone. In addition, patients in the CT+PT group showed signifi cant pre-post diff erences on positive and negative cognitive organization, an eff ect that was not evident in the antidepressant group. Th ese fi ndings suggest that cognitive therapy is able to modify cognitive structures that previous research has shown are stable into remission (Dozois, 2007; Dozois & Dobson, 2001a). Although these results are in need of replication, they do suggest that cognitive therapy alters conceptually deeper cognitive structures than does antidepressant medication. Th is deeper cognitive change may be one reason that cognitive therapy operates as a better prophylaxis against relapse than pharmacotherapy (cf. Gloaguen et al., 1998).
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In addition to results of diff erential mood-reactivity and cognitive structure are neuroimaging data on changes in cognitive therapy (see DeRubeis et al., 2008; and Frewen, Dozois, & Lanius, 2008, for reviews). Goldapple et al. (2004), for instance, examined the neurobiological responses to cognitive therapy (in unmedicated de- pressed outpatients) and compared these fi ndings to an independent sample of indi- viduals treated with selective serotonin reuptake inhibitors (SSRIs). Th ese researchers found diff erent pre- vs. post-treatment changes in the metabolic activity (Positron Emission Tomography) of individuals treated with cognitive therapy compared to those treated with antidepressant medication. Goldapple et al. proposed that a top- down (cortical-limbic) therapeutic mechanism may have been active in cognitive therapy, whereas a bottom-up (limbic-cortical) mechanism may have active in anti- depressant treatment.