Today many authors argue that these and other common elements are even more powerful than the features that distinguish one therapy from another. To take just one example, Wampold concluded in a 2001 analysis that the therapeutic alliance—the strength of the bond between a therapist and his or her client—accounts for about 7 percent of therapeutic effectiveness but that the school of the therapy accounts for only about 1 percent. Most of the remaining 92 percent is presumably caused by other factors, such as the personalities of the therapist and client.
Is the Dodo Bird Extinct?
Although most researchers agree that common factors play key roles in psychotherapy, some doubt that all methods are equally effective. Even Wampold has been careful to note that his conclusion holds for only bona fide treatments; it does not extend to all 500 or so therapies. For example, few experts would contend that rebirthing therapy, premised on the dubious idea that we must “relive” the trauma of our birth to cure neurosis, works as well as cognitive-behavior therapy for most psychological conditions.
Moreover, research suggests that even among accepted therapies, the type of treatment does matter under certain circumstances. A 2001 review by University of Pennsylvania psychologist Dianne Chambless and Virginia Polytechnic Institute psychologist Thomas Ollendick revealed that behavior therapy and cognitive-behavior therapy are more effective than many, and probably most, other treatments for anxiety disorders and for childhood and adolescent depression and behavioral problems. In addition, in a 2010 meta-analysis psychologist David Tolin of the Institute of Living in Hartford, Conn., found that these same two therapy types produce better results than psychodynamic therapy for anxiety and mood disorders.
The Dodo Bird verdict must also be qualified by evidence indicating that several widely used therapies do not work and may actually harm. For example, in a 2003 review psychologist Richard McNally of Harvard University and his colleagues evaluated crisis debriefing. In this treatment for warding off post-traumatic stress symptoms, therapists urge those exposed to emotionally fraught events such as shootings or earthquakes to try to reexperience the feelings they had during the event soon after it. McNally's team concluded that this treatment is inert at best and possibly damaging, perhaps because it interferes with natural coping mechanisms.
In light of such findings, a search for a therapist should at least sometimes involve a consideration of the type of treatment he or she practices. It is true that ingredients, such as empathy, that cut across effective therapies are potent and that various established techniques are roughly equivalent for a broad range of difficulties. Yet under certain circumstances, the therapeutic method can matter. For example, if a clinician espouses an approach outside the scientific mainstream—one that does not fall under the broad categories we have listed here—you should not assume that this treatment will be as helpful as others. If you suffer from an anxiety disorder or one of the other conditions for which behavior and cognitive-behavior interventions work well, then someone who practices one of those two types is probably a good bet.
Of course, scientists have systematically assessed only a minority of the psychotherapies invented so far for their efficacy in treating the numerous psychological difficulties that afflict humankind. In the coming decade, we hope that further research clarifies whether the brand of therapy makes a difference in an individual's recovery from psychological distress.
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