Is Psychotherapy Effective?
Investigators have overwhelmingly concluded that psychotherapy is generally helpful. Most clients improve by the end of psychotherapy. Specifically, Wampold (2001), in his review of the literature, found that the average client who was in psychotherapy was psychologically healthier than were 79% of untreated individuals. Wampold concluded that “psychotherapy is remarkably efficacious” (p. 71).
Once researchers established conclusively that psychotherapy in general is indeed helpful, they began to examine the relative effectiveness of different types of therapy. To date, hundreds of studies have compared different types of treatment (e.g., client-centered, psychodynamic, cognitive–behavioral, experiential), but no one type of therapy has been found to be more effective than others (Lambert, 2013; Wampold, 2001; Wampold et al., 1997). Wampold noted, however, that the treatments studied were all sanctioned forms of treatment rather than fringe or quack forms of treatment, so these results may not hold for nonmainstream treatments. Similarly, no differences have been found between individual and group treatments (Piper, 2008; M. L. Smith, Glass, & Miller, 1980). The findings from this area of research have been humorously summarized using the dodo bird verdict from Alice in Wonderland: “Everyone has won and all must have prizes” (Carroll, 1865/1962, p. 412).
It is probably hard to understand how therapies that are so different can all lead to the same outcomes. Many different reasons have been proposed for the lack of differences across approaches. The most currently popular explanation is that factors involved in all types of mainstream approaches (i.e., common factors) lead to positive outcomes. Frank and Frank (1991) discussed six factors that are common across psychotherapies: the therapeutic relationship, instillation of hope, new learning experiences, emotional arousal, enhancement of mastery or self- efficacy, and opportunities for practice. Thus, although therapists from different orientations espouse different philosophies and use somewhat different skills, the most important factor may be what therapists do in common.
Another explanation for the lack of differences among psychotherapeutic approaches is that client and therapist factors explain more of the variance than do treatment types (again, see Wampold, 2001). Thus, differences among therapists and clients may be more important than the approach used.
Yet another explanation (and one that I personally prefer) is that our research is still at a rather primitive state and that our tools for examining the process and
outcome of therapy are not sophisticated enough to pick up the differences between approaches. It is quite possible that all approaches can be helpful and lead to similar outcomes but do so through different mechanisms. For example, experiential therapy might heal through allowing deep immersion into feelings, which then leads the client to change thoughts and behaviors. By contrast, cognitive–behavioral therapy might begin with changes in thoughts and behaviors, which in turn lead to a change in emotions. Furthermore, different therapists and clients may prefer approaches that fit with their worldviews and personality styles.
Another interesting line of research involves how many psychotherapy sessions are needed to reduce psychological distress and return the client to normal psychological functioning (e.g., Grissom, Lyons, & Lutz, 2002; Howard, Lueger, Maling, & Martinovich, 1993; Kopta, Howard, Lowry, & Beutler, 1994). In their reviews of a large number of studies, these researchers proposed three phases of the psychotherapeutic recovery process. In the first phase, clients change rapidly in terms of feeling subjectively better. In the second, slower phase, there is a remediation of symptoms such as depression and anxiety. In the third and slowest phase, there is rehabilitation of troublesome, maladaptive behaviors that interfere with life functioning in areas such as family and work. Clients with minimal distress improve fairly quickly, whereas clients with chronic characterological problems (i.e., innate, severe, ongoing, and difficult-to-treat disorders) require the greatest number of sessions to return to normal functioning.
In his review, Lambert (2013) found that 50% of clients who were in the dysfunctional range at the beginning of therapy achieved clinically significant change after 20 sessions of therapy. He noted, however, that it takes more than 50 sessions for 75% of initially dysfunctional clients to reach clinically significant change. It is interesting that positive mental health is rarely mentioned in these studies but is an important index of outcome.