Background: In the past few decades, a considerable number of studies have examined the effects of psychotherapies for adult depression.
Aim: We described the results of a series of meta-analyses examining what this large body of research has contributed to our knowledge of these treatments of depression.
Results: We found that different types of psychotherapy are efficacious in the treatment of adult depression, including cognitive behavior therapy, interpersonal psychotherapy, problem-solving therapy, non-directive supportive therapy and behavioral activation therapy. Differences between types of psychotherapy are small. The efficacy of psychotherapy for mild to moderate depression is about the same as the efficacy of pharmacotherapy, and that combined treatment is more effective than psychotherapy alone and pharmacotherapy alone. Psychotherapy is not only effective in depressed adults in general, but also in older adults, women with postpartum depression, patients with general medical disorders, in inpatients, in primary care patients, patients with chronic depression and in subthreshold depression.
Conclusions: We found no evidence showing that psychotherapy is less efficacious in severe depression (with mean baseline Hamilton Depression Rating Scale scores up to 31, mean Beck Depression Inventory scores up to 35.85 and mean Beck Depression Inventory-II scores up to 36.50), but effects are smaller in chronic depression. We also found that the effects of psychotherapy are probably overestimated because of publication bias and the relatively low quality of many studies in the field.