Stefan G. Hofmann, PhD
Department of Psychological and Brain Sciences, Boston University
Steven C. Hayes, PhD
Department of Psychology, University of Nevada, Reno
The Inter-Organizational Task Force on Cognitive and Behavioral Psychology Doctoral Education, organized by the Association for Behavioral and Cognitive Therapies (Klepac et al., 2012), marks an important step in the arduous journey of clinical psychology toward a mature applied science. The task force developed guidelines for integrated education and training in cognitive and behavioral psychology at the doctoral level in the United States, which seem to us to open up important avenues of training.
A series of important consensus processes has marked the development of evidence-based intervention approaches. A milestone on this journey was the 1949 Boulder conference, which officially recognized that clinical psychology training should emphasize both the practice and the science of the profession (Raimy, 1950). Soon after, in 1952, Hans-Jürgen Eysenck delivered a somber challenge to the nascent field of clinical psychological science in his review of the effectiveness of adult psychotherapies, concluding that psychotherapy was not more effective in treating clients than the simple passage of time:
In general, certain conclusions are possible from these data. They fail to prove that psychotherapy, Freudian or otherwise, facilitates the recovery of neurotic patients. They show that roughly two-thirds of a group of neurotic patients will recover or improve to a marked extent within about two years of the onset of their illness, whether they are treated by means of psychotherapy or not. This figure appears to be remarkably stable from one investigation to another, regardless of type of patient treated, standard of recovery employed, or method of therapy used. From the point of view of the neurotic, these figures are encouraging; from the point of view of the psychotherapist, they can hardly be called very favorable to his claims. (pp. 322–323)
Eysenck was known for his strong bias against psychoanalysis, and the development of behavior therapy was, at least in part, an attempt to rise to his challenge. The first behavior therapy journal, Behaviour Research and Therapy, appeared in 1965, and within a few years Eysenck’s original question—Does psychotherapy work?—changed to a much more specific and difficult question (Paul, 1969, p. 44): “What treatment, by whom, is most effective for this individual with that specific problem, and under which set of circumstances, and how does it come about?” Behavior therapists, and later, cognitive behavioral therapists, pursued at least part of that question by studying protocols of various specific disorders and problems.
By the time Smith and Glass (1977) performed the first meta-analysis of psychotherapy outcomes, they were able to examine 375 studies, representing approximately 25,000 subjects, and to calculate an effect-size analysis based on 833 effect-size measures. The results of this impressive analysis show clear evidence of the efficacy of psychotherapy beyond merely waiting. On average, a typical patient receiving any form of psychotherapy was better off than 75 percent of untreated people, and overall the various forms of psychotherapy (systematic desensitization, behavior modification, Rogerian, psychodynamic, rational emotive, transactional analysis, and so on) were equally effective.
Since then, psychotherapy research has evolved considerably. Enhancements have been made in clinical methodologies and research design, our understanding of diverse psychopathologies, psychiatric nosology, and assessment and treatment techniques. Government agencies, insurance companies, and patient advocate groups have begun to demand that psychological interventions be based on evidence. In line with the more general move toward evidence-based medicine (Sackett, Strauss, Richardson, Rosenberg, & Haynes, 2000), in psychotherapy the term evidence-based practice considers the best available research evidence for the effectiveness of a treatment, the specific patient characteristics of those receiving the treatment, and the clinical expertise of the therapist delivering the treatment (American Psychological Association Presidential Task Force on Evidence-Based Practice, 2006). Various agencies and associations worldwide have begun compiling lists of evidence-based psychotherapy methods, such as the National Registry of Evidence-based Programs and Practices (NREPP) of the US Substance Abuse and Mental Health Services Administration.
In a highly influential step in 1995, the Society of Clinical Psychology (Division 12 of the American Psychological Association) created a Task Force on Promotion and Dissemination of Psychological Procedures with the goal of developing a list of research-supported psychological treatments (RSPTs; earlier names for this list were evidence-supported treatments and evidence-based treatments). It should be noted that the Division 12 task force deliberately recruited clinicians and researchers from a number of different theoretical orientations, including psychodynamic, interpersonal, cognitive behavioral, and systemic points of view, in order to avoid allegiance biases (Ollendick, Muris, & Essau, in press).
The Division 12 task force published its first report in 1995, in which it included three categories of RSPTs: (1) well-established treatments, (2) probably efficacious treatments, and (3) experimental treatments. Well-established treatments had to be superior to a psychological placebo, drug, or other treatment, whereas the probably efficacious treatments had to be superior only to a wait-list or no-treatment control condition. Well-established treatments were also required to have evidence from at least two different investigatory teams, whereas probably efficacious treatments were required to have evidence from only one investigatory team. Moreover, the task force required that all treatments specify patient characteristics (such as age, sex, ethnicity, diagnosis, etc.) and that treatment manuals explain the specific treatment strategies. Although not strictly required, the list of RSPTs was largely based on treatments for specific disorders defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM; American Psychiatric Association, 2000, 2013).
Finally, it was necessary for treatments to demonstrate clinical outcomes in well-controlled clinical trials or in a series of well-controlled single-case designs. The quality of the designs had to be such that the benefits observed were not due to chance or confounding factors, such as the passage of time, the effects of psychological assessment, or the presence of different types of clients in the various treatment conditions (Chambless & Hollon, 1998). This system of treatment categorization was intended to be a work in progress. Consistent with this goal, the list of RSPTs was placed online and is now maintained and updated at http://www.div12.org/psychological-treatments/treatments.
Most recently, the criteria for RSPTs were revised to include evidence from meta-analytic reviews of multiple trials across multiple domains of functioning (Tolin, McKay, Forman, Klonsky, & Thombs, 2015). Of all treatments, cognitive behavioral therapy (CBT) has by far the largest evidence base. A review of the efficacy of CBT for mental disorders easily filled a large three-volume textbook series (Hofmann, 2014b). It should be noted, however, that some disorders are more responsive to existing CBT methods than others. In the case of anxiety disorders, for example, a meta-analysis of methodologically rigorous, randomized, placebo-controlled studies reported that CBT yields the largest effect sizes for obsessive-compulsive disorder and acute stress disorder but only small effect sizes for panic disorder (Hofmann & Smits, 2008). Moreover, some CBT protocols show disorder specificity; for example, depression changes to a significantly lesser degree than anxiety with a protocol targeting anxiety disorders, and the reverse is true for depressive disorders. This clearly speaks against the argument that CBT lacks treatment specificity. At the same time, this and many other meta-analyses show that there is clearly a lot of room for improvement with contemporary CBT (Hofmann, Asnaani, Vonk, Sawyer, & Fang, 2012).
Despite the well-planned and executed mission, the Division 12 task force report and its list-supported treatments generated heated debates and arguments. Some of the counterarguments focused on fears that the use of treatment manuals would lead to mechanical, inflexible interventions and a loss of creativity and innovation in the therapy process. Another frequently made argument was that treatments that were effective in clinical research settings might not be transportable to “real-life” clinical practice settings with more difficult or comorbid clients (for a review, see Chambless & Ollendick, 2001). The strong representation of CBT protocols (in contrast to psychodynamically or humanistically oriented therapies) among the treatments meeting the RSPT criteria also fueled the intensity of the debates. A final major concern for some psychotherapists was the alignment of empirically supported treatments with specific diagnostic categories.
For example, consider the difference between CBT and psychodynamically oriented therapies. Instead of trying to identify and resolve hidden conflicts, CBT practitioners could encourage clients to utilize more-adaptive strategies to deal with their present psychological problems. As a result of this relative concordance, CBT protocols were developed for virtually every category of the DSM and the tenth revision of the International Statistical Classification of Diseases and Related Health Problems (ICD-10; World Health Organization, 1992–1994).
A recent review of the literature identified no fewer than 269 meta-analytic studies examining CBT for nearly every DSM category (Hofmann, Asnaani et al., 2012). In general, the evidence base of CBT is very strong, especially for anxiety disorders, somatoform disorders, bulimia, anger control problems, and general stress, because CBT protocols closely align with the different psychiatric categories. Although generally efficacious, there are clear differences in the degree of CBT’s efficacy across disorders. For example, major depressive disorder and panic disorder manifest a relatively high placebo-response rate. Such disorders run a fluctuating and recurring course so that the important question is not so much what are the short-term outcomes, since many treatments may work initially, but rather how effective are treatments in preventing relapse and recurrence in the longer term (Hollon, Stewart, & Strunk, 2006).
The focus on DSM-defined psychiatric disorders has sometimes limited the vision of CBT in its measures and application. For example, with CBT, measures of flourishing, quality of life, prosociality, relationship quality, or other issues that are more focused on growth and prosperity are often less in focus despite client interest in such issues. This limited vision is especially true of behavioral measures, which is unfortunate, because we know that some of the methods used in evidence-based therapy are applicable to health and prosperity issues.
The focus on disorders has led to a proliferation of specific protocols that can make training difficult and can limit the integration of research and clinical literature. Practitioners can get lost in a sea of supposedly distinctive but often overlapping methods.
These issues of breadth of focus, long-term effects, and protocol proliferation touch upon some fundamental ideas about the nature of psychological functioning and of treatment goals. It is the claim of this volume that the field needs a course correction to rise to the challenges of the present moment.
The development and refinement of CBT models for the various DSM and ICD-10 diagnoses has permitted therapists and researchers to apply specific treatment techniques across a diverse range of psychopathologies. However, the general alignment of CBT protocols with the medical classification system of mental disorders has had downsides (e.g., Deacon, 2013). For example, classifying people using criteria-based psychiatric diagnostic categories based on presenting symptoms minimizes or ignores contextual and situational factors contributing to the problem (e.g., Hofmann, 2014a). Modern CBT often overemphasizes techniques for specific symptoms at the expense of theory and case conceptualization, limiting the further development of CBT. Health promotion and the whole person can become less of a focus as syndromal thinking dominates. CBT is not at an end state; rather, it needs to continue to evolve with time, generating testable models (Hofmann, Asmundson, & Beck, 2013) and novel treatment strategies (e.g., Hayes, Follette, & Linehan, 2004).
Some authors argue that clinical researchers developing research-based interventions largely ignore common factors (as opposed to specific treatment strategies), and that these factors are primarily responsible for therapeutic change (Laska, Gurman, & Wampold, 2014). Approaching this issue as a dichotomy appears to be an error. It is actually relatively common for clinical researchers developing empirically supported treatments to consider these factors by examining the effects of, for example, the therapeutic alliance in outcomes. The impact of common factors varies from disorder to disorder, and although they can be important, they alone are not sufficient to produce the maximum effects on treatment outcomes. Furthermore, relationship factors can be responsive to the same psychological processes that evidence-based methods target. This suggests that the theoretically coherent processes addressed by CBT may in part account for some common factors. For example, the mediating relationship of the working alliance is no longer significant to outcome if a client’s psychological flexibility is added as an additional mediator (e.g., Gifford et al., 2011), suggesting that the therapeutic alliance works in part by modeling acceptance, nonjudgment, and similar processes that may be targeted in modern CBT methods.
Much of the data on the therapeutic alliance is correlational and points to relatively immutable features, such as therapist variables. Common factors become central to practitioners, however, when specific methods to change them are developed and tested against other evidence-based methods. That kind of work is just beginning, and to conduct that work better, therapists need to develop theories about the therapeutic alliance and how, concretely, to change it—precisely the kinds of areas where CBT and evidence-based therapy can be helpful.
It is time for clinical psychology and psychiatry to move beyond picking either common factors or evidence-based psychological treatments in an all-or-none analysis (Hofmann & Barlow, 2014). Instead, we need to isolate and understand the effective processes of change and how best to target them, with relationship factors treated as one such process. This approach will allow the field to focus on any issue that will help our clients improve their lives and will help advance our scientific discipline.
In the early days of behavior therapy, specific problems or specific positive growth targets were often the aim of the intervention, but with the rise of the DSM, syndrome and mental disorders became more of a focus. Clinical scientists have engaged in a long and heated debate over how to best define and classify mental disorders (e.g., Varga, 2011). The structure of the DSM-5 and ICD-10 is firmly rooted in the biomedical model, assuming that signs and symptoms reflect underlying and latent disease entities. Earlier versions of these manuals were grounded in psychoanalytic theory, assuming that mental disorders are rooted in deep-seated conflicts. In contrast, the modern versions implicate dysfunctions in genetic, biological, psychological, and developmental processes as the primary causes of a mental disorder.
A prominent sociobiological definition of the term mental disorder is “harmful dysfunction” (Wakefield, 1992). The problem is considered a “dysfunction” because having it means that the person cannot perform a natural function as designed by evolution; the problem is considered “harmful” because it has negative consequences for the person, and society views the dysfunction negatively.
Not surprisingly, this definition is not without criticism because it is unclear how to define and determine the function or dysfunction of a behavior (e.g., McNally, 2011). Early critics (e.g., Szasz, 1961) argued that psychiatric disorders are simply labels that society attaches to normal human experiences and represent essentially arbitrary social constructions without any functional value. The same phenomenon that is considered abnormal in one culture or at one point in history may be considered normal or even desirable in another culture or at another point in history.
The official definition of a mental disorder in the DSM is “a syndrome characterized by clinically significant disturbance in an individual’s cognition, emotion regulation, or behavior that reflects a dysfunction in the psychological, biological, or developmental processes underlying mental functioning” (American Psychiatric Association, 2013, p. 20). Although this definition specifically mentions psychological and developmental processes as possible primary causes in addition to biological ones, psychiatry has long operated primarily within a biomedical framework.
The cognitive behavioral approach is most commonly based on a diathesis-stress model, which assumes that an individual’s vulnerability factors in conjunction with particular environmental factors or stressors can lead to the development of the disorder. This perspective makes a critical distinction between initiating factors (i.e., the factors that contribute to the development of a problem) and maintaining factors (i.e., the factors that are responsible for the maintenance of a problem) (Hofmann, 2011). These two sets of factors are typically not the same. Unlike other theoretical models of mental disorders, CBT is generally more concerned about the maintenance factors because they are the targets of effective treatments for present impairments. Therefore, from a CBT perspective, classifying individuals based on maintenance factors is likely to be of far greater importance than classifying individuals based on vulnerabilities alone, such as genetic factors or brain circuits.
This emphasis is broadly in line with the developmental approach of the behavioral tradition, which may not emphasize vulnerabilities and stressors but recognizes that the historical factors that led to a problem may differ from the environmental factors that maintain it. Functional analysis is focused on maintaining factors for current behaviors precisely because it is these that need to change in order to improve an individual’s mental health.
Proponents of the DSM often point out that a psychiatric classification system, no matter how imprecise, is a necessity for the following reasons: First, it provides the field with a common language to describe individuals with psychological problems. This is of great practical value because it simplifies communication among practitioners and provides a coding system for insurance companies. Second, it advances clinical science by grouping together people with similar problems in order to identify common patterns and isolate features that distinguish them from other groups. Third, this information may be used to improve existing treatments or to develop new interventions. This latter purpose is acknowledged by the DSM-5, which states, “The diagnosis of a mental disorder should have clinical utility: it should help clinicians to determine prognosis, treatment plans, and potential treatment outcomes for their patients” (American Psychiatric Association, 2013, p. 20). Despite these lofty goals, however, the DSM-5 offered little new or different material from its predecessors, sparking a great degree of dissatisfaction in the medical and research community.
Aside from political and financial issues (the DSM is a major source of income for the American Psychiatric Association), there are many theoretical and conceptual problems with the DSM. For example, it pathologizes normality using arbitrary cut points; a diagnosis made using the DSM is merely based on subjective judgment by a clinician rather than objective measures; it is overly focused on symptoms; its categories describe a heterogeneous group of individuals and a large number of different symptom combinations that define the same diagnosis, and most clinicians continue to use the residual diagnosis (“not otherwise specified”) because most clients do not fall neatly into any of the diagnostic categories, which are derived by consensus agreement of experts (for a review, see Gornall, 2013).
Perhaps one of the biggest conceptual problems is comorbidity (i.e., the co-occurrence of two or more different diagnoses). Comorbidity is inconsistent with the basic notion that symptoms of a disorder reflect the existence of a latent disease entity. If disorders were in fact distinct disease entities, comorbidity should be an exception in nosology. However, disorders are commonly comorbid. For example, among mood and anxiety disorders, the DSM-5 posits that virtually all of the considerable covariance among latent variables corresponding to its constructs of unipolar depression, generalized anxiety disorder, social anxiety disorder, obsessive-compulsive disorder, panic disorder, and agoraphobia can be explained by the higher-order dimensions of negative and positive affect; this suggests that mood and anxiety disorders emerge from shared psychosocial and biological/genetic diatheses (Brown & Barlow, 2009).
Observations like these served as the basis for recent efforts to develop so-called transdiagnostic (Norton, 2012) or unified (Barlow et al., 2010) treatment protocols that cut across diagnostic categories to address the core features of disorders, the goal being to develop more parsimonious and, perhaps, powerful treatments (Barlow, Allen, & Choate, 2004). In addition, this approach might counter the drawback of training clinicians in disorder-specific CBT protocols, which often leads to an oversimplification of human suffering, inflexibility on the part of the clinician, and low adherence to evidence-based practices (McHugh, Murray, & Barlow, 2009).
In an attempt to offer a solution to the nosology problems associated with the DSM (and the ICD-10), the National Institute of Mental Health (NIMH) developed the Research Domain Criteria (RDoC) Initiative, a new framework for classifying mental disorders based on dimensions of observable behavior and neurobiological measures (Insel et al., 2010). This initiative is an attempt to move the field of psychiatry forward by creating a classification system that conceptualizes mental illnesses as brain disorders. In contrast to neurological disorders with identifiable lesions, mental disorders are considered disorders with abnormal brain circuits (Insel et al., 2010). Instead of relying on clinical impressions, resulting in arbitrarily defined categories that comprise heterogeneous and overlapping diagnostic groups, the NIMH suggests integrating the findings of modern brain sciences in order to define and diagnose mental disorders (Insel et al., 2010).
The stated goal of this project is to develop a classification system for mental disorders based on biobehavioral dimensions that cut across current heterogeneous DSM categories. The RDoC framework assumes that dysfunctions in neural circuits can be identified with the tools of clinical neuroscience, including electrophysiology, functional neuroimaging, and new methods for quantifying connections in vivo. The framework further assumes that data from genetics and clinical neuroscience will yield biosignatures that can augment the clinical symptoms and signs used for clinical management. For example, in the case of anxiety disorders, the practitioner of the future would utilize data from functional or structural imaging, genomic sequencing, and laboratory-based evaluations of fear conditioning and extinction to determine a prognosis and appropriate treatment (Insel et al., 2010). The concrete product of the RDoC initiative is a matrix that lists different levels (molecular, brain circuit, behavioral, and symptom) of analysis in order to define constructs that are assumed to be the core symptoms of mental disorders.
Whereas neuroscientists generally applauded the RDoC initiative (Casey et al., 2013), others criticized it for various reasons. For example, the project overemphasizes certain kinds of biological processes, reducing mental health problems to simple brain disorders (Deacon, 2013; Miller, 2010). So far the RDoC has had limited clinical utility because it is primarily intended to advance future research, not to guide clinical decision making (Cuthbert & Kozak, 2013). Moreover, the RDoC initiative shares with the DSM the strong theoretical assumption that psychological problems (“symptoms”) are caused by a latent disease. In the case of the DSM, these latent disease entities are measured through symptom reports and clinical impressions, whereas in the case of the RDoC they are measured through sophisticated behavioral tests (e.g., genetic tests) and biological instruments (e.g., neuroimaging).
In the last few decades, considerable progress has been made to identify core dimensions of psychopathology. The RDoC initiative proposes such a dimensional classification system. Similarly, psychologists have been reconsidering dimensions of psychopathology. For example, in the case of emotional disorders, numerous authors have identified emotion dysregulation as one of the core transdiagnostic problems (Barlow et al., 2004; Hayes, Luoma, Bond, Masuda, & Lillis, 2006; Hayes, Strosahl, & Wilson, 1999; Hofmann, Asnaani et al., 2012; Hofmann, Sawyer, Fang, & Asnaani, 2012). This is fully consistent with contemporary emotion research, such as the process model described by Gross (1998). Gross’s emotion-generative process model of emotions posits that emotion-relevant cues are processed to activate physiological, behavioral, and experiential responses, and that these responses are modulated by emotion regulation tendencies. Depending on the time point at which a person engages in emotion regulation, the techniques are either antecedent-focused or response-focused strategies. Antecedent-focused emotion regulation strategies include cognitive reappraisal, situation modification, and attention deployment and occur before the emotional response has been fully activated. In contrast, response-focused emotion regulation strategies, such as strategies to suppress or tolerate the response, are attempts to alter the expression or experience of an emotion after the response has been initiated.
There are many more pathology dimensions that cut across DSM-defined disorders, such as negative affect, impulse control, attentional control, rumination and worrying, cognitive flexibility, self-awareness, or approach-based motivation to name only a few. As these dimensions have become more central to the understanding of psychopathology, it has become clearer that employing in a flexible manner the strategies that are most appropriate for a given context and goal pursuit is the most adaptive method for long-term adjustment (Bonanno, Papa, Lalande, Westphal, & Coifman, 2004). Many forms of psychopathology are associated with the negatively valenced responses, such as fear, sadness, anger, or distress, but all of these play a positive role in life. No psychological reaction, and no strategy for addressing a psychological reaction, is consistently adaptive or maladaptive (Haines et al., 2016). The goal of modern CBT is not to eliminate or suppress feelings, thoughts, sensations, or memories—it is to promote more positive life trajectories. Learning how best to target relevant processes that foster positive growth and development is the challenge of modern intervention science and the focus of this volume.
It appears that the fundamental question of psychotherapy research formulated by Hans-Jürgen Eysenck (1952), and then revised by Gordon Paul (1969), needs to be revised yet again. The core question is no longer whether intervention works in a global way, nor is it how to make effective technological decisions in a contextually specific manner. The first question has been answered, and the technological emphasis of the second has led to a proliferation of methods that are difficult to systematize in a progressive fashion. Because of their failure to identify functionally distinct entities, both the purely syndromal focus and the largely technological approach need to be de-emphasized.
The movement toward the RDoC contains a key aspect that seems to fit this moment of evolution in the field of psychotherapy. The complex network approach also offers another potentially promising new perspective on psychopathology and treatment (Hofmann, Curtiss, & McNally, 2016). Instead of assuming that mental disorders arise from underlying disease entities, the complex network approach holds that these disorders exist due to a network of interrelated elements. An effective therapy may change the structure of the network from a pathological to a nonpathological state by targeting core processes. Similar to traditional functional analysis, we need to understand the causal relationship between stimuli and responses in order to identify and target these core processes of pathology and change in a contextually specific way. Longitudinal designs are allowing clinicians to develop targeted and specific measures that predict the development of psychopathology over time (e.g., Westin, Hayes, & Andersson, 2008). Clinicians can target these measures for change using evidence-based methods and determine the mediating role of change in these processes (e.g., Hesser, Westin, Hayes, & Andersson, 2009; Zettle, Rains, & Hayes, 2011).
By combining strategies, such as RDoC, functional analysis, the complex network approach, and longitudinal design, researchers are making progress in identifying the core processes of change in psychotherapy and psychological intervention (Hayes et al., 2006). With increasing knowledge of the components that move targeted processes (e.g., Levin, Hildebrandt, Lillis, & Hayes, 2012), researchers are building on that foundation. The goal is to learn which core biopsychosocial processes should be targeted with a given client who has a given goal in a given situation, and to then identify the component methods most likely to change those processes.
The identification of core processes in psychotherapy will guide psychotherapists into the future. These processes will allow us to avoid the constraints of treatment protocols based on a rigid and arbitrary diagnostic system and will directly link treatment to theory. This vision is what animates the present volume—that is, creating a more process-based form of CBT and evidence-based therapy. This vision pulls together many trends that already exist in the field and builds on the strengths of the many traditions and generations of work that make up the cognitive and behavioral approaches to therapy.
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