Empirically Supported Treatments: Conceptions and Misconceptions
Empirically Supported Treatments: What are they?
Empirically supported treatments (ESTs) are interventions that have been found to be efficacious for one or more psychological conditions, like major depression, panic disorder, or obsessive-compulsive disorder. Prior to the 1990s, there were no specific guidelines for either practitioners or mental health consumers regarding which treatments to select for which conditions. As a consequence, the psychotherapy field was plagued by serious problems with quality control.
This state of affairs changed in 1993, when a task force appointed by the Society for Clinical Psychology (Division 12) within the American Psychological Association developed a set of criteria for, and provisional list of, what were then termed "empirically validated treatments," later termed ESTs. According to the current task force guidelines (Chambless & Hollon, 1998), ESTs are therapies that have demonstrated (a) superiority to a placebo (dummy treatment) in two or more methodologically rigorous controlled studies, (b) equivalence to a well-established treatment in several rigorous and independent controlled studies, or (c) efficacy in a large series of single-case controlled designs, that is, designs that systematically compare the effects of a treatment and with those of a control condition within subjects. The studies must be performed with treatment manuals that specify a reasonably clear "recipe" for how to conduct the intervention.
The Division 12 task force, originally chaired by Dr. Dianne Chambless, now lists 16 ESTs in total, with numerous other treatments listed as "probably efficacious." These ESTs include a number of behavioral and cognitive-behavioral therapies (CBTs), such as CBT for major depression, panic control treatment for panic disorder, and exposure and response prevention for obsessive-compulsive disorder. There is general (Kendall, 1998), although by no means universal (e.g., Westen, Novotny, & Thompson-Brenner, 2004), agreement among psychotherapy researchers that the movement toward ESTs is a necessary first step toward providing practitioners with guidelines for good psychotherapy practice.
ESTs: Misconceptions and Misunderstandings
Nevertheless, the push to develop lists of ESTs has been immensely controversial (Arkowitz & Lilienfeld, 2006) and has met with fierce resistance in some quarters. Although several of the criticisms of ESTs may have merit (see "ESTs: Future Directions"), several others appear to be premised on misunderstandings concerning the EST criteria. Below are some of the most widespread misconceptions regarding ESTs (see Chambless & Ollendick, 2001, and Weisz, Weersing, & Hengeller, 2005, for further discussions of these and other misconceptions).
- (1) Randomized controlled trials (RCTs), on which the EST list is based, are fallible and no more informative than other sources of evidence.
This claim is problematic on two fronts. First, as noted earlier, the EST list
does not require treatments to be tested using RCTs, as a series of rigorous single-case designs can also suffice. Second, the assertion that RCTs are no more informative than other sources of evidence is false, because RCTs control for a host of sources of error, such as placebo effects, spontaneous remission, regression to the mean, and demand characteristics.
- (2) The EST list is biased against psychodynamic therapies.
To some degree this accusation is true, although that is only because most psychodynamic therapies - those based largely on the theories of Sigmund Freud and his followers - have been inadequately researched and therefore have yet to accumulate a sufficient research base.
- (3) Because some treatments that haven't yet been studied may turn out to be efficacious, the EST list is unfair.
It is indeed true that one must distinguish unvalidated treatments - those that have yet to be adequately researched - from invalidated treatments - those that have been researched and shown not to work. The EST list does not imply that unvalidated treatments might not later become empirically supported with sufficient research; it implies only that such treatments have yet to prove their mettle. Nevertheless, it is crucial to recall that the burden of proof falls on proponents of treatments to show that they work, not on critics to show that they do not work. Hence, the argument that it is unfair to exclude unvalidated treatments from the EST list violates one of the most crucial standards of science: namely, that one should not accept claims without adequate evidence.
- (4) The EST list is unnecessary, because research shows that all psychotherapies work equally well.
In criticizing the EST list, some researchers have invoked the "Dodo Bird verdict," named after the Dodo Bird in "Alice and Wonderland," who said (following a race) that "Everybody has won and all must have prizes." According to the Dodo Bird verdict, all therapies work equally well, so the EST list is based on an erroneous premise - namely, that some therapies work better for certain disorders than others. Nevertheless, recent research has demonstrated that the Dodo Bird verdict is false. For example, studies show that behavioral and cognitive-behavioral treatments are more effective than other treatments for childhood disorders, and that exposure-based treatments - those that expose people to the stimuli that provoke their fears - are more effective than other treatments for obsessive-compulsive disorder, phobias, and several other anxiety disorders.
- (5) Some of the studies on which the EST list is based are flawed.
That is almost certainly true, although virtually all studies are flawed in certain respects. The goal of the EST list, like that of all advances in science, is to reduce uncertainty. Without this list, there is little or no explicit guidance to clinicians concerning which treatments to administer for which conditions. With this list, there is at least some scientifically informed guidance, which is superior to none. Imperfect but informative evidence is almost always better than no evidence at all.
- (6) ESTs are not generalizable to the real world.
Some critics have charged that research on "efficacy" - how well treatments perform in carefully controlled settings - do not generalize to research on "effectiveness" - how well they perform in real-world settings. In part, these critics suggest, that it is because the efficacy studies on which ESTs are based often exclude severely disordered patients or patients with "comorbid" (co-occurring) conditions. There is some truth to this criticism. Nevertheless, many recent efficacy studies have begun to examine patients with problems more closely resembling those in real-world settings. These studies have typically found that treatments with high efficacy also display high effectiveness.
- (7) Because ESTs are manualized, they necessarily constrain clinical creativity.
To some extent, this criticism is based on a caricature of manualized therapies. Treatment manuals do not necessarily mandate fixed responses to patients' verbal behaviors in therapy; instead, most manuals provide flexible guidelines for how to proceed at different stages of treatment. Moreover, increasing numbers of treatment manuals afford therapists considerable leeway to respond flexibly to differing patient trajectories within treatment.
- (8) The EST list is fixed and cannot change in response to new evidence.
The EST list is not a permanent list of efficacious treatments. Instead, it is a work in progress, subject to continual updating in light of new data. Indeed, one advantage of this list is that allows previously unresearched treatments to be listed as ESTs as supportive evidence becomes available.
ESTs: Future Directions
Thus, although many of the concerns with the American Psychological Association's approach to defining, identifying, and cataloguing ESTs are based on fundamental misunderstandings, there are alternative and complementary approaches that appear to have merit for connecting the research on children's mental health treatments to clinical practice. For example, some researchers have noted that many ESTs appear to differ only in their superficial features, and that a number of seemingly different treatments may work for the same underlying reasons. They have argued that a list of "empirically supported principles of change," such as the exposure to feared stimuli in many effective treatments for anxiety disorders or the restoration of hope in many effective treatments for depression, may ultimately be more fruitful than a list of ESTs (Rosen & Davison, 2003). There is considerable merit to this suggestion, although it will need to await stronger consensus among clinical scientists regarding the underlying mechanisms of change that cut across many therapies.
Similarly, other researchers have argued that the specific clinical techniques that comprise most ESTs appear to draw from a relatively limited number of procedures, and that there is merit to mapping the relationship between specific clinical procedures (e.g., cognitive restructuring, relaxation training) and client or contextual features (e.g., clinical problem, age, gender, setting) (Chorpita & Daleiden, 2009). This paradigm is seen as one that potentially complements a "list" approach, offering detail about the specific procedures that commonly characterize the numerous ESTs often applicable to a given area and pointing out what most ESTs do and do not have in common with one another.
Several research groups have begun to consider the question of how to define evidence for real-world systems, with some systems developing an expanded number of "levels of evidence" (Chorpita et al., 2002), and with some researchers emphasizing the importance of repeated measurement of client outcomes as a primary source of evidence (Bickman, 2008; Daleiden & Chorpita, 2005; Lambert, 2005).
Finally, the EST list is intended to inform practitioners and mental health consumers about effective treatments, but it does not warn them about potentially harmful treatments (Chorpita et al., 2002; Lilienfeld, 2007). For example, recent evidence suggests that that such widely used treatments as crisis debriefing for individuals exposed to trauma and "Scared Straight" programs for adolescents with conduct problems may make some clients worse. It may therefore be equally important to construct a list of potentially harmful treatments (PHTs), as consumers of psychotherapy need to be well informed about interventions that may harm as well as those that help.
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