A study published by the journal "Psychological Science in the Public Interest" compared a series of published studies on treatment and prevention of depression. The authors reported that cognitive therapy has performed satisfactorily in many controlled trials of fully clinical populations. Some of the literature reviewed by Hollon et al. (2002) suggests that cognitive therapy might be superior to antidepressants in some populations and that early meta-analyses have indicated its superiority to medications in reducing acute distress. Other studies reviewed by this article provide evidence that cognitive therapy and treatment with an SSRI have been found to be superior to placebo and did not differ in effectiveness from one another.
Hollon, S. D., Thase, M. E. & Markowitz, J. C. Treatment and prevention of depression.
Psychological Science in the Public Interest, 3, 2002.
The authors emphasize that cognitive therapy depends on the quality of its implementation and suggest that not all therapists seem to be able to implement it satisfactorily in patients with severe depressions. Differences in many studies have been found specifically among the population of severely depressed people, which according to Hollon et al (2002), helps support the case for therapist's expertise making a great difference depending on severity of symptoms in those populations.
Findings reported by Hollon, Thase, and Markowitz (2002) suggest that the effects of cognitive therapy tend to be enduring. According to the authors, "several studies have shown that patients treated to the point of remission with cognitive therapy are only about half as likely to relapse following termination of treatment as are patients who enter remission after treatment with medications" (p.63). Whether cognitive therapy is used contingently with medications or alone, its enduring effects on relapse and recurrence rates are an indication of the success of this method.
Cognitive Therapy versus
Antidepressant Medications
The article
also considered studies that analyzed the effects of cognitive behavioral
interventions on Endogenous versus Non-Endogeneous depression in combination
with medication. Hautzinger, de Jong-Meyer, Treiber, and Rudolf (1996)
reported that "cognitive therapy was as efficacious as medication and no
less effective than combined treatment in a sample of patients who did
not meet criteria for endogenous depression." Another study by the same
authors found that the addition of cognitive therapy to medication treatment
did little to enhance the effects of the latter in a sample of people with
endogenous features of depression (as cited in Hollon et al. 2002, p. 65).
Combination of medication and Cognitive Therapy or related cognitive behavioral interventions seem to be effective on certain kinds of patients, especially those with chronic depression (Hollon et al. 2002). According to the referenced article, Thase, Bowler, and Harden (1991) report that 80% of unmedicated patients with major depression responded to up to 20 sessions of cognitive therapy over a 4-week period (as cited in Hollon et al. 2002, p. 65). Bowers (1990) reported that adding cognitive therapy or a similar method such as relaxation to inpatients medication reduced depressive symptoms more than medication by itself (as cited in Hollon et al. 2002).
The graph below shows the
results of four randomized comparisons: Rush, Beck, Kovacs, and Hollon
(1977); Murphy, Simons, Wetzel, and Lustman (1984); Hollon et al. (1992);
Elkin et al. (1989). This graph summarizes the average response to cognitive
behavior therapy versus antidepressant medications in severe depression
cases. For more information on authors please check the aforementioned
article.
The authors of this graph report that treatment outcome was measured by posttreatment scores on the Hamilton Rating Scale for Depression. From "Medication Versus Cognitive Behavior Therapy for Severely Depressed Outpatients: Mega-Analysis of Four Randomized Comparisons" by R. J. DeRubeis, L. A. Gelfand, T. Z. Tang, and A. D. Simmons, 1999, American Journal of Psychiatry, 156, p. 1010. (as cited in Hollon et al, 2002, p. 63).
Hollon, S. D., Thase, M. E. & Markowitz, J. C. (2002). Treatment and prevention of
depression. Psychological Science in the Public Interest, 3, 2002.