This week I was reading the current issue of Clinical Psychology: Science and Practice, which included a large meta-analysis comparing different kinds of therapy for the treatment of depression in adults. I have previously discussed the concept of meta-analysis (see for example a review of this meta-analysis of the effectiveness of different parenting practices). In sum, a meta-analysis attempts to statistically group the results of all previous studies on a specific topic and reach an overall conclusion. This is a very valuable process since it allows us to make sense of the often conflicting information that is presenting by individual studies. In addition, meta-analyses help us understand variables that may explain why individual studies show different (often conflicting) results. For example, one study may indicate that x treatment works, while another study may indicate that the same treatment doesn’t work. A meta-analysis may identify a variable (e.g., age of participants) that explains the discrepancy (the first study may have been conducted with older person suggesting that the treatment is effective with older patients but not younger ones).
In the meta-analysis I was reading this week, Dr. Trevor Mazzucchelli compared several types of therapies including Behavioral Activation, Cognitive-Behavioral, and other interpersonal therapies in the treatment of depressed ADULTS. Behavioral Activation therapies are focused on changing behaviors (e.g., getting off the couch!) while Cognitive-Behavior Therapies (CBT) focus on changing both behaviors and how we “think” about events (e.g., helping us realize some of our thoughts – “no one loves me” – may be inaccurate). In contrast, Interpersonal therapies are varied, but often focus on the relationship between the therapist and the patient/client as catalyst for change. In Mazzucchelli meta-analysis, Behavioral Activation and Cognitive-Behavioral Therapy were significantly more effective than other therapies. However, the efficacy of Behavioral Activation and Cognitive-Therapy were not different than each other. This is consistent with previous findings that have suggested that the most effective interventions are “behavioral” in nature and that even within the famous Cognitive-Behavioral Treatment the “effective” component may be the “behavioral” rather than the “cognitive” part.
But what does this have to do with child psychology, after all, this meta-analysis was conducted with adults? My colleague and child depression specialist Maria Kovacs recently developed a new therapy intervention for youth, mostly responding to the poor effectiveness of current treatment interventions for depression in children and adolescents. For example, in 2006 Dr. John R. Weisz, from Harvard University published an extensive meta-analysis of the efficacy of therapies for child and adolescent depression (see below for the reference). The overall conclusion of that study was that treatment was better than no treatment, but the level of effectiveness was relatively poor. That is, child and adolescent therapy for depression was barely effective. This has prompted the creation of new intervention such as Kovac’s new program.
But the recent Mazzucchelli meta-analysis with adults made me reconsider the Waisz meta-analysis with children. Remember, with adults, Behavioral Activation was more effective than other interventions and equally effective than CBT. So I wonder if the original Waisz study also compared those 3 different modalities. The answer was “no”. Instead, due to the limited diversity of studies, the authors grouped cognitive therapies and compared them to all other therapies. They found that these were not different from each other. What is the problem? That there was no comparison between therapies that use mostly Behavioral Activation (the most effective in adults) and therapies that do not use behavioral activation (the least effective in adults). So it is possible that treatment for child and adolescent depression is better than we initially thought if we were to examine the effects of Behavioral Activation therapies alone (given the adult findings). Some would argue however that I should not apply the adult findings to children. In most cases this is a valid argument, but in this case there are theoretical and research evidence that would indicate that Behavioral Activation should be even MORE effective with children and adolescents. Specifically, a few studies have suggested that cognitive interventions for depression seems to be more effective as children get older, likely because developmental processes limit the use of cognitive interventions in young children. So it is possible that interventions that focus on behavioral activation, rather than cognitive restructuring, may lead to even better outcomes in the treatment of depression in children and adolescents.
One of my students is currently working on a preliminary review of previous depression treatment studies aiming to identify the level of effectiveness of behavioral therapies for depressed children and adolescents and compare them to cognitive and interpersonal therapies. Weisz, J., McCarty, C., & Valeri, S. (2006). Effects of Psychotherapy for Depression in Children and Adolescents: A Meta-Analysis. Psychological Bulletin, 132 (1), 132-149 DOI: 10.1037/0033-2909.132.1.132
Mazzucchelli, T., Kane, R., & Rees, C. (2009). Behavioral Activation Treatments for Depression in Adults: A Meta-analysis and Review Clinical Psychology: Science and Practice, 16 (4), 383-411 DOI: 10.1111/j.1468-2850.2009.01178.x