Worldwide, about 280 million people suffer from depression, with an economic cost of nearly $1 trillion per year due to loss of productivity. Clinical guidelines indicate that antidepressant medications and psychotherapy are the front-line treatments for depression. Over 1000 randomized controlled trials have been conducted to examine the effects of psychological therapies. Pim Cuijpers, a Dutch researcher, has been maintaining an extensive database of all studies of psychotherapies for depression and has conducted numerous meta-analyses over the past two decades. In this review, Cuijpers summarizes this large body of research. First, a striking finding is that despite new treatments for depression that have been developed, the effect sizes of psychological therapies have not improved over the past 50 years. This suggests that new psychological treatments have not enhanced patient outcomes. Second, although the uptake of psychological therapies has increased over the past decades in high-income countries, this increased use of psychotherapy has not resulted in a reduction in the prevalence of depression. Third, psychotherapies, including CBT, IPT, psychodynamic therapy, behavioural activation, and third-wave therapies, are equally effective for treating depression. Fourth, less than half of patients receiving psychological treatment respond. That is, approximately 41% of patients improve due to treatment (i.e., with 50% lower symptoms at post-treatment), in contrast to 17% improvement in those who receive no therapy. This indicates that psychotherapy has an incremental effect (added value) of 24%. Fifth, there are no significant differences in delivery format (face-to-face, virtual) as long as there is contact with a human. Interventions without human support might be somewhat effective but with significantly smaller effects. Sixth, psychotherapy and antidepressant medications have comparable outcomes, but psychotherapy is more effective in the longer term (1 year post-treatment). The combination of psychotherapy and antidepressants is more effective than either therapy alone, but the incremental value of combining the two is small.
The effects of psychotherapy for depression are modest, with therapy resulting in better outcomes for 41% of patients, representing a 24% added value compared to no treatment. This is essential information for clinicians to moderate theirs and their patient’s expectations. By comparison, the effects of psychotherapy are similar to those of standard medical treatments for health problems. There is currently no reason to choose one brand of therapy over another, and this choice perhaps should be guided by patients’ preferences. Also, if a patient does not respond to a specific type of psychotherapy, then a different kind of psychotherapy should be tried next. There may be no benefit to clinicians being trained in a “new” type of psychotherapy, as new treatments over the past 50 years have not resulted in greater improvements in patients’ depression. Psychotherapy is more effective when delivered by a human than by a computer program.
Cuijpers, P. (2024). How to improve outcomes of psychological treatment of depression: Lessons from “next-level” meta-analytic research. American Psychologist, 79(9), 1407–1417. https://doi.org/10.1037/amp0001387.