Is CBT Worthless?

According to a new meta-analysis in Psychological Medicine (Lynch et al., 2009), Cognitive Behavioral Therapy (CBT) is not helpful for those with schizophrenia and bipolar disorder, and any improvements seen in major depression are rather small:

Conclusions: CBT is no better than non-specific control interventions in the treatment of schizophrenia and does not reduce relapse rates. It is effective in major depression but the size of the effect is small in treatment studies. On present evidence CBT is not an effective treatment strategy for prevention of relapse in bipolar disorder.

CBT is a form of psychotherapy that attempts to change the patient's unhealthy thoughts and actions. The patient learns to identify distorted thought patterns and beliefs, and to replace them with more productive ways of thinking and acting. Frequently the treatment is very brief, and also "highly structured, problem orientated and prescriptive, and individuals are active collaborators." The short duration of 5-20 weeks in most cases is appealing to insurance companies. Previous studies have endorsed CBT as one of the most effective treatments for major depression and many other disorders (see this review of CBT meta-analyses by Butler et al., 2006). Recommendations for CBT primarily as an adjunct treatment in schizophrenia are fewer, and have been more common in the UK (Rosack, 2002) than in Canada and the US (but see Rector & Beck, 2002). CBT may have beneficial effects during the depressive phase of bipolar disorder, but previous studies have been variable and inconclusive (Miklowitz & Scott, 2009).

Lately we've been treated to a plethora of articles and press releases saying that antidepressants are worthless and no better than placebo. The present meta-analysis by Lynch et al. (2009) came to the same conclusion about CBT in schizophrenia, and ratcheted down its effectiveness in major depression. The press release is quite blunt:

Cognitive Therapy Is Of No Value In Schizophrenia, Analysis Of Studies Suggests

ScienceDaily (June 26, 2009) — Research co-led by an academic at the University of Hertfordshire, concludes that cognitive behavioural therapy (CBT) is of no value in schizophrenia and has limited effect on depression.

. . .

The results of the review suggest that not only is CBT ineffective in treating schizophrenia and in preventing relapse, it is also ineffective in preventing relapses in bipolar disorder.

The review also suggests that CBT has only a weak effect in treating depression, but it has a greater effect in preventing relapses in this disorder.

The meta-analysis included studies examining the effectiveness of CBT against symptoms in schizophrenia and depression, and in reducing relapse in schizophrenia, depression, and bipolar disorder. Rigorous criteria were used when selecting only well-conducted clinical trials of CBT for inclusion:

The studies were required to use a control intervention that the study investigators either explicitly considered not to have specific therapeutic effects or which might reasonably be regarded as lacking these (e.g. supportive therapy, psycho-education, relaxation). We also included studies comparing CBT to pill placebo (which have only been carried out in major depression). Blindness of evaluations was not specified as a requirement for inclusion, but was examined as a moderator variable. In keeping with the general approach of meta-analysing methodologically rigorous trials, we did not include studies with small sample sizes (less than 10 participants in either group) or studies that were identified by the authors as pilot studies.

Lynch et al. provided a list of excluded studies in their Supplementary Materials, and I imagine there will be much debate in the field over the inclusion and exclusion criteria. The authors end on a cautionary note:

The authors of meta-analyses of CBT for depression seem unperturbed by the fact that they are basing their conclusions on studies that have often been carried out against TAU [treatment as usual] or a waiting list control; that have not always been randomized; that sometimes failed to use diagnostic criteria; and that so far have ignored the moderating effect of blindness altogether. These issues are not trivial; the findings of our meta-analysis could be viewed as an object lesson on the importance of taking such sources of bias into account.

References

Butler AC, Chapman JE, Forman EM, Beck AT. (2006). The empirical status of cognitive-behavioral therapy: a review of meta-analyses. Clin Psychol Rev. 26:17-31.

Lynch, D., Laws, K., & McKenna, P. (2009). Cognitive behavioural therapy for major psychiatric disorder: does it really work? A meta-analytical review of well-controlled trials. Psychological Medicine DOI: 10.1017/S003329170900590X.

Miklowitz DJ, Scott J. (2009). Psychosocial treatments for bipolar disorder: cost-effectiveness, mediating mechanisms, and future directions. Bipolar Disord. 11 Suppl 2:110-22.

Rector NA, Beck AT. (2002). A clinical review of cognitive therapy for schizophrenia. Curr Psychiatry Rep. 4:284-92.

Rosack J (2002). Psychiatrists Assess CBT As Schizophrenia Treatment. Psychiatric News 37:18