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The Great Psychotherapy Debate: Since in April, 2015 I review parts of The Great Psychotherapy Debate (Wampold & Imel, 2015) in the PPRNet Blog. This is the second edition of a landmark, and sometimes controversial, book that surveys the evidence for what makes psychotherapy work. You can view parts of the book in Google Books.

Wampold, B.E. & Imel, Z.E. (2015). The great psychotherapy debate: The evidence for what makes psychotherapy work (2^nd edition). New York: Routledge.

In this part of the book, Wampold and Imel discuss the importance of client expectations on psychotherapy outcomes. In particular, they equate client expectations with the placebo effect. In the July, 2015 PPRNet blog, I discussed Wampold and Imel’s distinction between the Contextual Model of psychotherapy and the Medical Model of psychotherapy. One pathway of the Contextual Model indicates that patients who accept an explanation for their disorder and who agree with therapists about therapy interventions, experience expectations that have a powerful impact on patients’ emotions and cognitions. The placebo effect has long been known to improve patients’ response to medical interventions. The placebo effect is defined as the difference between a supposedly inert event or medication and the natural course of the disorder. By contrast, the specific effect of an intervention or medication (e.g., an antidepressant) is defined as the difference between the medication and the placebo (i.e., the effect of a medication over and above the effect of a placebo). In one important meta analysis, the placebo effect accounted for about 68% of the antidepressants’ impact on depression scores. In other words, the placebo effect (i.e., the expectation of receiving help) has a powerful impact on depression. Generating an expectation of improvement (“this pill is an antidepressant that will reduce your depression”) involves: (1) providing a plausible explanation for the disorder (“depression is biochemical imbalance, and this pill [actually an inert placebo] will help”), and (2) having a relationship with an empathic provider. Client expectations of improvement result in mental health outcomes that approach the effects of standard medical treatment for depression. In psychotherapy, creating expectations about the effectiveness of the intervention, providing an explanation of the disorder based on psychological and biological theories, and agreeing on the tasks and goals of therapy are an integral part of the treatment. In other words, the placebo response is part of what makes psychotherapy work, and good therapists capitalize on its effects.

Practice Implications

Patient expectations about the effectiveness of the therapy, their agreement with the therapist on the tasks and goals of therapy, and the therapist’s empathy toward the patient are key aspects that will increase the effectiveness of a therapeutic intervention. The explanation of the disorder and the treatment approach are embedded in psychological theories that typically underpin evidence-based psychotherapies.

Johnsen, T. J., & Friborg, O. (2015, May 11). The effects of cognitive behavioral therapy as an anti-depressive treatment is falling: A meta-analysis. Psychological Bulletin. Advance online publication. http://dx.doi.org/10.1037/bul0000015

Depression is a highly debilitating disorder and ranked third in terms of disease burden in the world. Cognitive behavioral therapy (CBT) is an effective treatment for depression that was introduced over 40 years ago. In part, CBT sees depression as caused by maladaptive thoughts that maintain emotional distress and dysfunctional behavior. Reducing depression is achieved by eliminating the impact of or chancing maladaptive thoughts. CBT is the most researched psychological treatment for depression, and the research goes back several decades. A number of technical variations and new additions have been made over the years to CBT to improve patient outcomes. The volume of research and its history provides a unique opportunity to assess time trends in the effects of CBT. In this meta analysis, Johnsen and Friborg asked: “have the effects of CBT changed over time”? They also looked at whether client factors (e.g., demographics, symptom severity), therapist factors (e.g., age, experience, training), common factors (e.g., therapeutic alliance, client expectancies), and technique factors (e.g., fidelity to a treatment manual) can explain these trends. Johnsen and Friborg reported on 70 studies of 2,426 patients conducted from 1977 to 2014. Males accounted for 30.9% of patients, 43% had comorbid psychiatric conditions, and the average patient was at least moderately depressed. The average effect of CBT in reducing depression was large (g = 1.46 after accounting for publication bias). Women had better outcomes, studies with poorer methodological quality showed larger effects, and patients of more experienced therapists had better outcomes. There were too few studies measuring therapeutic alliance to assess the effect of common factors on outcomes. Most interesting was a significant relationship between effect sizes and year of publication. That is, the effects of CBT declined significantly over the years, though the average effect remained large. Surprisingly, there was a steeper decline for studies that used a treatment manual compared to those that did not. No other variables were reliably associated with this decline.

Practice Implications

Women and patients of more experienced therapists appear to benefit most from CBT. Although the effects of CBT declined over time, the treatment remained highly effective. Johnsen and Friborg’s study could not easily explain this decline. The authors suggested that the placebo effect (expectation on the part of patients, researchers, and therapists) is typically stronger for new treatments. However, as time passes the strong initial expectations tend to wane thus reducing the overall effect of the intervention. They also suggested that CBT treatment outcomes may be improved not by technical variations and new additions, but by better ways of integrating common, therapist, and client factors.

Author email: tjj@psykologtromso.no

Rutherford, B.R., Pott, E., Tandler, J.M., Wall, M.M., Roose, S.P., & Lieberman, J.A. (2014). Placebo response in antipsychotic clinical trials: A meta-analysis. JAMA Psychiatry, doi:10.1001/jamapsychiatry.2014.1319.

The placebo response refers to improvements in symptoms among participants in medication trials that cannot be specifically attributed to the active ingredient of the intervention. For this reason, it is common to have a placebo control condition in trials of medications. In these trials, some participants are randomly assigned to the medication condition, and some are randomly assigned to a placebo control condition. Typically, the placebo is a pill that looks exactly like the medication but that has no active ingredient. Both patients and providers are blind or unaware of whether the patient is receiving the active medication or the placebo. The placebo response is usually attributed to a number of sources: (1) the patient’s expectation of receiving benefit, (2) the patient’s contact with a caring provider and the healing effect of factors like therapeutic alliance and provider empathy, (3) statistical and measurement error, and (4) random changes in patient symptoms that are unrelated to the medication or the placebo. The first two sources are psychological factors that are often specifically active and purposefully enhanced in psychotherapies. That is, some psychotherapists actively work to develop an alliance with the patient and to align therapeutic interventions with patient expectations and preferences. (For a broader discussion, see my review of Common Factors in this month’s PPRNet blog.) The placebo response can sometimes be quite powerful such that antidepressant medications, and antipsychotic medications for example, only tend to be modestly superior to placebo. People with schizophrenia have cognitive difficulties that may reduce their expectations of receiving benefits from treatment. These patients also have significant interpersonal difficulties so that their alliance with health care providers may be significantly hampered. For these reasons, it may be possible that the placebo response may play a smaller role in the medical treatment of patients with schizophrenia. Rutherford and colleagues conducted a meta analysis of 105 studies of over 24,000 participants from 1960 to the present. Their goal was to examine if the average drug-placebo difference decreased significantly over time (i.e. across years of publication). They found that the placebo response significantly increased from 1960 to the present. That is, the average placebo patient tended to get worse in the 1960s, but by the 2000s the average placebo participant tended to get better. The effect of this trend was large (r = .52). By contrast, treatment change associated with antipsychotic medications decreased over time, and the effect of this trend was moderate (r = -.26). The authors suggested possible explanations for this trend. The average participant in drug trials in the 1960s was more severely ill than the average patient enrolled in drug trials in the 2000s. It is possible that the placebo response is more powerful in less severely ill individuals. Also, the authors suggested that a number of study design factors (e.g., multi site vs single site trials, financial incentives to recruit more patients may result in less severely ill and younger samples) may also contribute to this trend.

Practice Implications

One of the practical implications of these findings is that drug companies may be less inclined to fund research and development of new medications for mental illnesses if the research is increasingly showing only modest benefits over control conditions. On the other hand, health care workers who provide: support and empathy, a positive therapeutic alliance, positive expectations about benefits of treatment, attention to patient preferences, and a coherent narrative to understand their patient’s illness may help to enhance the effects of interventions including antipsychotic medications. This may be especially true for younger and less severely ill individuals with schizophrenia.