Chapter 29

Future Directions in CBT and Evidence-Based Therapy

Steven C. Hayes, PhD

Department of Psychology, University of Nevada, Reno

Stefan G. Hofmann, PhD

Department of Psychological and Brain Sciences, Boston University

In the early days of the behavior therapy movement, the late Gordon Paul, then just a few years past his PhD, wrote one of the most quoted questions about the proper goal of a science of evidence-based interventions (1969, p. 44): “What treatment, by whom, is most effective for this individual with that specific problem, under which set of circumstances, and how does it come about?” We included this quote in chapter 1 because it opened the door to a scientific approach to therapeutic intervention that links contextually specific evidence-based procedures to evidence-based processes that solve the problems and promote the prosperity of particular people. This approach did not quite go far enough, however, because in the early days of behavior therapy there was far too much trust that learning principles and theories was an adequate basis for clinical procedures. Indeed, that may explain why two years earlier Paul (1967) hadn’t included the phrase “and how does it come about” in the original formulation of this question, instead focusing entirely on contextually specific evidence-based procedures. Processes of change were an afterthought.

A truly process-based approach gives high priority to evidence-based processes and to evidence-based procedures as they are linked to these processes. At this point in the volume, we are finally in a position to put a fine point on the foundational question the field of clinical change needs to focus on in order to make a priority choice. The central question in modern psychotherapy and intervention science now is “What core biopsychosocial processes should be targeted with this client given this goal in this situation, and how can they most efficiently and effectively be changed?” Answering these questions is the goal of any form of process-based empirical therapy, but we argue that it is now, most especially, becoming the goal of processes-based cognitive behavioral therapy (CBT).

Relieving human suffering is a challenging goal in every way. It requires powerful conceptual tools that will parse human complexity into a manageable number of issues. It requires clinical creativity that will lead to the successful targeting of key domains and dimensions of human functioning. It depends on methodological tools that permit the development of generalizable knowledge from detailed experience with myriad individuals.

In the early days, learning principles and an artful approach to functional analysis were the bulk of what was available to take this approach, and they simply were not enough. The principles and procedures were too limited, and linking principles and procedures with individuals—a task in itself—needed more bolstering from science. In the decades that followed, the behavioral movement expanded its conceptual and procedural armamentarium, becoming CBT as a result. That was a step forward, although as we explored in section 2 of this book, the field is still learning how best to develop and use a more catholic set of principles and to organize them into pragmatically useful forms; and, as we showed in section 3, many modern procedures are only now coming into their own, scientifically speaking.

Government agencies also wanted to see the development of evidence-based therapy (EBT), but they had their own ideas about how to do so, driven largely by ideas from the psychiatric establishment. After the third version of the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders was developed in 1980, the US National Institute of Mental Health (NIMH) decided to pour resources into funding randomized trials of specific protocols targeting psychiatric syndromes. This combination had an enormous impact on the field of CBT, and on EBT more generally, bringing prestige and attention to psychotherapy developers but also inadvertently narrowing their vision.

In the grand arc of history, these developments did a lot of good for the field. The study of protocols for syndromes captured some of the essence of Paul’s agenda, and there was an enormous increase in the amount of data available about psychotherapy and other psychosocial interventions, the impact of psychiatric medications, the development of psychopathology, and other key issues. Among other things, the concerns raised by Eysenck (1952) about whether evidence-based psychotherapy could be shown to be better than doing nothing at all were answered once and for all. CBT was a prime beneficiary of this growth of evidence, leading to its current position as the best-supported intervention approach.

The biomedicalization of human suffering that underlay these developments, however, left behind several key features of Paul’s clinical question. The new question—“What protocol is best for the symptoms of this syndrome?”—intervention scientists were answering failed to capture adequately the needs of the individual, the context of interventions, the specificity of procedures, the specificity of problems, and the link to processes of change. In other words, protocol- and syndrome-based empirical therapy left behind a number of the defining features of a process-based empirical therapy approach.

The field is still dealing with the practical and intellectual challenges that resulted. Theory suffered as a more purely technological approach blossomed. How important are processes and principles if they are just used as a vague setup for technologies and are not formally tested as moderators and mediators of intervention? The inability to develop robust theories of behavior change should be expected if theory development is merely an untested ritual engaged in before the real action of protocol development linked to syndromes occurs.

As the new research program unfolded in the thirty-year period between 1980 and 2010, it was extremely discouraging, scientifically speaking, that a focus on syndromes never seemed to lead to conclusive evidence on etiology, course, and response to treatment. Said in another way, a syndromes approach never led to the discovery of diseases, which is the ultimate purpose of syndromal classification. Comorbidity and client heterogeneity was so great within syndromal groups that traditional diagnosis felt more like an empty ritual than a vitally important and progressive process. After 2010 the NIMH began withdrawing its interest—in effect, abandoning the very approach it had taken on board as its developmental strategy thirty years earlier, bringing CBT researchers along for the ride. The DSM-5 was released in 2013 with a notable lack of enthusiasm in almost every corner of the field.

CBT has gone through changes as well. In this book we avoided the language of the “third wave” because it can feel offensive to some in the field, and our entire goal is to try to bring the different wings and traditions together under a more process-based approach. Still, it is worth looking beyond reactions to that specific label for the new generation of work that was emerging within CBT (Hayes, 2004); the key features that these developments emphasized are ways to possibly improve understanding and outcomes. An original, italicized statement summarizing third-wave ideas emphasized that what was emerging was an “empirical, principle-focused approach…[that] is particularly sensitive to the context and functions of psychological phenomena…and reformulates and synthesizes previous generations of behavioral and cognitive therapy and carries them forward into questions, issues, and domains previously addressed primarily by other traditions” (Hayes, 2004, p. 658). Stated another way, CBT had arrived at a point where a process-based empirical approach could be used to open up the tradition to the full range of issues that can be examined in EBT.

The present volume attempts to step forward in that way. A process-based approach reflects to some degree the pressures that have led the NIMH to focus on the framework of the Research Domain Criteria Initiative instead of the DSM as a way forward (Insel et al., 2010), but it does so by taking intervention science in a process-based direction. We organized the book around the recent consensus document (Klepac et al., 2012) of the Inter-Organizational Task Force on Cognitive and Behavioral Psychology Doctoral Education, in part, because that document shows how the field at large is developing greater sophistication about what is needed to reorient the field in a post-DSM era.

When theory and processes of change became more central, the task force correctly argued that more training is needed in philosophy of science, scientific strategy, ethics, and the broad range of domains from which principles can arise. More training is needed in linking procedures to principles, and in fitting procedures to the particular needs of the particular case in an ethical and evidence-sensitive manner. We agree with the task force’s conclusions, and the chapters in this volume are in part an effort to respond to that challenge. This book is not a comprehensive response—that will take a whole series of volumes, of which this is the first we plan to publish.

At this point in the volume it is worth considering what the future may hold if the field develops a greater empirical linkage between procedures and processes that alleviate problems and promote prosperity in people. Stated another way: What will unfold in an era of process-based empirical therapy? We cannot say for sure, but the broad outlines seem clear enough. In several areas, the chapters in the present volume anticipate some of the changes that appear to lie ahead.

Likely Future Developments

The decline of named therapies. As packages and protocols are broken down into procedures linked to processes, named therapies will become much less dominant. Indeed, the term “cognitive behavioral therapy” has become too narrow because the therapeutic change that occurs is by no means restricted to cognitive and behavioral processes; there are also social, motivational, emotional, epigenetic, neurobiological, evolutionary, and many other evidence-based processes involved. Many of these have been outlined in the chapters of this book.

One could further argue that CBT is not a singular term, but that there are many CBTs, some more evidence based, theory grounded, and process oriented than others. But allowing evidence-based treatment to continue to develop under a mountain of specifically named treatments (e.g., eye movement desensitization and reprocessing, cognitive processing therapy, dialectical behavior therapy, and so on) will keep the field stuck in an era of packages and protocols. Those names that are linked to well-developed and specific theoretical models can be accommodated as names for theoretical models, but in a process-based era there is just no need to name every technological combination and sequence, any more than there is a need to name every architectural design or layout of city roads.

Very few of the chapters in section 3 present methods that would need to be linked to a named therapy in order to be effective. Chapter 3 emphasizes that clinicians often need to move beyond protocols by using case formulation that specifies how evidence-based treatment targets will be linked to robust processes of change. Named protocols will continue to have a role for some time, but as procedures and processes take center stage, most of them will begin to move to the sidelines.

The decline of general theories and the rise of testable models. Amorphous systems and general theoretical claims will either fold into more specific and testable models and theories or be recognized as broad philosophical claims. Distinct sets of philosophical assumptions will remain distinct, precisely because assumptions establish the grounds for empirical testing and thus are not fully subject to empirical testing (this issue is covered extensively in chapter 2 on the philosophy of science). This reality does not mean that philosophically distinct approaches cannot coexist and even cooperate. In this volume we argue that cooperation is more likely if differences in assumptions are appreciated. In some ways this very volume is a test of that idea by bringing together methods from the different wings and traditions in CBT.

Testable models and specific theories are highly useful in science, especially if more of an eye is given to their utility. In the era of syndromal protocols, theory was often given short shrift as it bore on intervention. That seems sure to change going forward. Pragmatically useful models and theories will be subjected to great scrutiny on several key dimensions, however, including the next four we are about to mention.

The rise of mediation and moderation. Even now, with the handwriting on the wall, agencies and associations that certify evidence-based intervention methods, such as Division 12 (clinical psychology) of the American Psychological Association, have failed to require evidence of processes of change linked to the underlying theoretical model and procedures deployed (Tolin, McKay, Forman, Klonsky, & Thombs, 2015). That cannot continue in a process-based era. Theoretical models that underlay an intervention procedure need to specify the processes of change linked to that procedure for a particular problem. Even if the procedure works well, if the specified process of change cannot be shown to be consistently applicable, the underlying model is wrong. The field can tolerate short delays while measurement issues are worked out, but the task of developing adequate assessment falls on those proposing models and theories, not on those properly demanding evidence for processes of change.

The distinction between a model failure and a procedural failure is important in the other direction as well. For example, if a procedure fails to alter putatively critical processes of change that may have been shown to be important in longitudinal studies of developmental psychopathology, then the model remains untested even if the procedure fails. In this case, the field can tolerate short delays while procedural details are worked out to produce better impact on processes of change in specific areas.

The most important point is that a procedure should be thought of as evidence based only when science supports that procedure, its underlying model, and their linkage. If a procedure reliably produces gains and manipulates a process that mediates these gains, then it is ready to be admitted into the armamentarium of process-based empirical therapy.

Even then, there is more to do on practical grounds. If moderation is not specified, it still needs to be investigated vigorously because the history of evidence-based methods shows that few processes are always positive regardless of context (e.g., Brockman, Ciarrochi, Parker, & Kashdan, 2016). Thus, in a mature, process-oriented field, evidence of theoretically coherent mediators and moderators will be as important as evidence of procedural benefits. We look forward to the day when meta-analyses of procedural mediation are as common and as important as meta-analyses of procedural impact.

New forms of diagnosis and functional analysis. As process-based approaches evolve, core processes that are used in new forms of functional analysis, and person-based applications, will become more central. The rise of statistical models that can delve into individual growth curves and personal cognitive and behavioral networks holds out the hope for a reemergence of the individual in evidence-based approaches. For example, the complex network approach can offer an alternative to the latent disease model. This approach holds that psychological problems are not expressions of underlying disease entities but rather are interrelated elements of a complex network. This approach, which is an extension of functional analysis, not only provides a framework for psychopathology, but it might be used to predict therapeutic change, relapse, and recovery at some point in time (Hofmann, Curtiss, & McNally, 2016).

We need an approach for targeting interventions that is not so much transdiagnostic (a term with feet placed uncomfortably across a divide that seems likely to widen) as it is an alternative approach to diagnosis. For process-based CBT and EBT to prosper, well-developed alternatives to the DSM that can guide research and practice are needed.

From nomothetic to idiographic approaches. Contemporary psychiatric nosology, which views psychiatric problems as expressions of latent disease entities, forces a nomothetic system onto human suffering. Consistent with this approach, in the protocol for syndrome-era CBT, protocol X was developed to treat psychiatric disease X, whereas CBT protocol Y was developed to treat disease Y, while all but ignoring any differences among individuals.

However, in order to answer Paul’s (1969) clinical question, a purely top-down, nomothetic approach will not be useful. This question requires a bottom-up idiographic approach in order to understand why in a particular case a psychological problem is maintained and how the change process can be initiated. Nomothetic principles are key, but their basis and their application need to include the intense analysis of the individual. Often qualitative research will inform these developments. Psychologists are already well equipped with many of the methodological tools to deal with these issues, ranging from single-case experimental designs (Hayes, Barlow, & Nelson-Gray, 1999) to ecological momentary assessments, and the use of these methodological tools will likely increase, especially as they are linked to modern statistical methods, as we noted with the immediately preceding trend.

Processes need to specify modifiable elements. The practical needs of practitioners present the field with a natural analytic agenda. This is one reason that different philosophies of science (see chapter 2) can more readily coexist within CBT than in many other areas of science: contextualists may view pragmatic outcomes as truth criteria in and of themselves, whereas elemental realists may view them as the natural outgrowth of ontological knowledge, but both can agree on the practical importance of the outcomes for intervention work. One implication is that processes that are clearly modifiable, and theories and models that specify contextual elements that can be used to modify processes of change, are inherently advantaged in a process-based approach to empirical therapy. Cognitions, emotions, and behavior are all the dependent variables of intervention science. Awareness of that simple fact adds the next key feature.
The importance of context. If a dependent variable is going to change in psychology, ultimately it needs to be done by changing history or situational circumstance. Said in another way, context needs to change. That is exactly what a therapeutic technique does.

Intervention scientists are far better at measuring the emotional, cognitive, or behavioral responses of people than they are at measuring the historical, social, and situational context. That is understandable, but the latter needs continuing attention in a process-based approach.

This truism about measuring suggests that theories and models that specify the relationship of processes of change to methods of manipulating these processes should be advantaged over theories and models that leave off this key step. Identifying this relationship is a demanding criterion that few current models and theories meet. It is easier to develop models of change that are not specifically tied to intervention components.

To some degree process-based therapy can solve this problem empirically: trial and error can determine which components move which change processes. In the long run, however, we need to know why certain methods move certain processes, not just that they do. Theories that explain the link between evidence-based processes and evidence-based procedures and components will thus become more important as a process-based empirical approach matures.

Component analyses and the reemergence of laboratory-based studies. The considerations we have touched on are part of why carefully crafted component studies have had a reemergence in CBT. It is possible to drill down in a very fine-grained way to specific process-based questions with clinical populations in the laboratory, but doing so in randomized controlled trials of packages and protocols would be harder to do (e.g., Campbell-Sills, Barlow, Brown, & Hofmann, 2006). It is unwise to allow packages to exist for many years before they are dismantled, but in a more process-based era, information about component processes can be built from the bottom up, allowing even a meta-analysis of scores of component studies to inform clinical work (Levin, Hildebrandt, Lillis, & Hayes, 2012).
Integration of behavioral and psychological science with the other life sciences. Behavioral and psychological science does not and cannot live in a world unto itself: behavior is part of the life sciences more generally. The enormous increase in attention to the neurosciences in modern intervention science reflects this more holistic and biologically friendly zeitgeist—in the modern era we want to know how psychological events change us as organisms and vice versa. There are other shoes still to fall, however, that are part of this same zeitgeist. We know, for example, that epigenetic processes impact the organization of the brain (Mitchell, Jiang, Peter, Goosens, & Akbarian, 2013), but they are themselves affected by experiences that are protective in mental health areas (e.g., Dusek et al., 2008; Uddin & Sipahi, 2013). Some of this is covered in chapter 10, on evolution science.

An interest in biology does not need to be reductionistic. History and context are as important to an evolutionary biologist as they are to a psychotherapist; this is one reason why we included a chapter on evolution science in this volume. Every level of analysis has its own place in a unified fabric of science. In the modern era, however, it’s likely that intervention scientists will be increasingly called upon to be broadly trained in the life sciences and to be knowledgeable about developments in them.

New forms of delivery of care. As chapter 4 on the changing role of practice shows, the world of apps, websites, telemedicine, and phone-based intervention is upon us. For decades psychotherapy trainers have worried that there will never be enough psychotherapists to go around given the enormous human need for psychological care. That sense of overwhelming need only increases when we think of global mental health needs, or when we realize that therapy methods are relevant to social problems (e.g., prejudice) or to human prosperity (e.g., positive psychology and quality of life).

Fortunately, there is no reason to think of psychotherapy as being limited to a fifty-minute, one-on-one, face-to-face intervention. Human beings can change because they read a book (Jeffcoat & Hayes, 2012), use an app on their smartphone (Bricker et al., 2014), or receive a short follow-up call from a nurse (Hawkes et al., 2013). A process-based approach is able to encompass these methods because of the relatively controlled research strategies that can document and study process changes as these methods are used, and because of the branching, interactive, and dynamic possibilities that many forms of technological intervention permit.

A science of the therapeutic relationship. As discussed in chapter 3, the therapeutic relationship and other common core processes themselves require an analysis. It is not enough to know that general therapy features predict outcome; common core processes need to be manipulated and shown to matter experimentally. As we mentioned in the book’s introduction, evidence-based intervention methods are having an impact on our understanding of the therapeutic relationship itself (Hofmann & Barlow, 2014). For example, it has been shown empirically that psychological flexibility can account for the impact of acceptance and commitment therapy, but it can also help account for the impact of the therapeutic alliance (e.g., Gifford et al., 2011).
Using the clinic as a source of data. CBT research began in the clinic. A process-based empirical approach seems likely to empower practitioners to stay involved in knowledge generation, especially as more individually focused analytic methods continue to emerge. Diversity matters in a process-focused approach, and front-line practitioners see a more diverse group of clients than do academic medical centers in large urban areas.
Using the world community as a source of data. Only a few countries on the planet can afford the kind of grant infrastructure that funds large, well-controlled outcome studies. All are in the West, and all are dominantly white. Yet at the same time, the world is awakening to the enormous health needs around the globe, including mental and behavioral health needs.

It is important to examine whether processes of change in EBT are culture bound—in the main, the answer so far appears to be reassuring (e.g., Monestès et al., 2016). Process-based empirical therapy holds out hope that it can better fit itself to the needs of and draw additional information from the world community. For example, if a process mediates outcome and it’s culturally valid, clinical creativity can be put to use figuring out how to best move that process in culturally sound and contextually appropriate procedures that are adjusted to fit specific needs.

The change of CBT as we know it. Ironically, over time a process-based approach seems likely to shorten the life of CBT as a clearly distinct approach compared with EBT more generally. This will not occur because all evidence-based methods will be shown to emerge from CBT. Rather, as CBT reorients toward issues that were previously the focus only of other therapy traditions, there will be fewer and fewer reasons to distinguish CBT from analytic, existential, humanistic, or systemic work.

There will always be a need for clarity about philosophical assumptions, but many theoretical systems already exist within CBT, and better training in philosophy of science should empower CBT researchers to walk into the lion’s den of more diverse theoretical systems without losing balance and bearing. We are not (yet) calling for an end to the use of the term “cognitive behavioral therapy.” If the approach contained within this volume is pursued, however, we can see a day when the term will add little to our description of the current field. It is possible that if all the trends discussed in this volume unfold, it will mean the end of CBT as we know it—but this will only be the case if considerable progress is made toward a new and empowering future of a broader and deeper form of EBT.

We are not sure if all these trends will unfold, nor if they will do so anytime soon. Many of them are already under way, however, so there can be no doubt that the world of psychological intervention is going to change. In the main, we believe that these trends are positive, and a more process-focused approach will help today’s students push out the boundaries of tomorrow’s consensus. The goal is not upheaval; the goal is progress. People are in need and are seeking answers from our field. It is up to us to provide for them. We hope this volume offers not just a snapshot of where we are today but also shines a beacon toward a place where we can go.

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Steven C. Hayes, PhD, is Foundation Professor in the department of psychology at the University of Nevada, Reno. An author of forty-four books and over 600 scientific articles, his career has focused on an analysis of the nature of human language and cognition, and the application of this to the understanding and alleviation of human suffering and the promotion of human prosperity. Among other associations, Hayes has been president of the Association for Behavioral and Cognitive Therapies (ABCT), and the Association for Contextual Behavioral Science. He has received several awards, including the Impact of Science on Application Award from the Society for the Advancement of Behavior Analysis, and the Lifetime Achievement Award from the ABCT.

Stefan G. Hofmann, PhD, is a professor in Boston University’s department of psychological and brain sciences clinical program, where he directs the Psychotherapy and Emotion Research Laboratory (PERL). His research focuses on the mechanism of treatment change, translating discoveries from neuroscience into clinical applications, emotions, and cultural expressions of psychopathology. He is past president of the Association for Behavioral and Cognitive Therapies (ABCT), and the International Association for Cognitive Psychotherapy. He is also editor in chief of Cognitive Therapy and Research, and is associate editor of Clinical Psychological Science. He is author of many books, including An Introduction to Modern CBT and Emotion in Therapy.