care.4, 6, 7 Unlike many of these other treatments, the benefits of cognitive behavioural intervention were broad ranging and maintained at 12 months, suggesting that these benefits will translate into substantial health gain at a population level.
Butler, A. C. & Beck, J. S. (2001). Tidsskrift for Norsk Psykologforening, 38(8), 698-706.
Fourteen meta analyses were reviewed to investigate the efficacy of cognitive therapy for various disorders. Findings indicate that cognitive therapy is substantially superior to no-treatment, wait list, and placebo controls for unipolar depression, generalized anxiety disorder, panic disorder, social phobia, and childhood depressive and anxiety disorders. Cognitive therapy was somewhat superior to antidepressants in the treatment of adult depression and had half the relapse rate 1 yr after treatment.
Stewart, R. E. & Chambless, D. L. (2009). Journal of Consulting and Clinical Psychology, 77(4), 595-606.
The efficacy of cognitive–behavioral therapy (CBT) for anxiety in adults is well established. In the present study, the authors examined whether CBT tested under well-controlled conditions generalizes to less-controlled, real-world circumstances. Fifty-six effectiveness studies of CBT for adult anxiety disorders were located and synthesized. Meta-analytic effect sizes are presented for disorder-specific symptom measures as well as symptoms of generalized anxiety and depression for each disorder, and benchmarked to results from randomized controlled trials. All pretest–posttest effect sizes for disorder-specific symptom measures were large, suggesting that CBT for adult anxiety disorders is effective in clinically representative conditions. Six studies included a control group, and between-groups comparisons yielded large effect sizes for disorder-specific symptoms in favor of CBT. Benchmarking indicated that results from effectiveness studies were in the range of those obtained in selected efficacy trials. To test whether studies that are more representative of clinical settings have smaller effect sizes, the authors coded studies for 9 criteria for clinical representativeness. Results indicate an inverse relationship between clinical representativeness and outcome, but the magnitude of the relationship is quite small.
Magill, M. & Ray, L. A. (2009). Journal of Studies on Alcohol and Drugs, 70(4), 516-527.
Objective: This meta-analysis examined 53 controlled trials of cognitive-behavioral treatment (CBT) for adults diagnosed with alcohol- or illicit-drug-use disorders. The aims were to provide an overall picture of CBT treatment efficacy and to identify client or treatment factors predictive of CBT effect magnitude. Method: The inverse variance weighted effect size (Hedges’ g) was calculated for each study and pooled using fixed and random effects methods. Potential study-level moderators were assessed in subgroup analyses by primary drug, type of CBT, and type of comparison condition. In addition, seven client and treatment variables were examined in meta-regression analyses. Results: Across studies, CBT produced a small but statistically significant treatment effect (g = 0.154, p < .005). The pooled effect was somewhat lower at 6-9 months (g = 0.115, p < .005) and continued to diminish at 12-month follow-up (g = 0.096, p < .05). The effect of CBT was largest in marijuana studies (g = 0.513, p < .005) and in studies with a no-treatment control as the comparison condition (g = 0.796, p < .005). Meta regression analyses indicated that the percentage of female participants was positively associated and the number of treatment