The Diagnostic System, by Jason Schnittker (framework)

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to the future, he joins with others in urging scientists to “set [their] sights higher” and aim for “precision” medicine.10 It is tempting, too, to regard public beliefs as evolving in much the same fashion as science. In many respects, public beliefs regarding mental illness are more sophisticated than they were in the past. Thirty years ago the representation of people with mental illness in the media was hardly flattering, and the stigma surrounding psychiatric disorders was strong. Many of the public’s beliefs betrayed a level of ignorance that is hard to imagine today. In 1972, Thomas Eagleton withdrew as George McGovern’s vice presidential running mate over concerns regarding his earlier treatment for depression.

Today, having received treatment for a psychiatric disorder is perhaps less concerning. Indeed, if taking psychiatric medications was summarily disqualifying, there would be far fewer capable politicians and professionals. In addition, public-opinion data reveal a more attuned and responsive culture.

Whereas the public was once ill informed, it is now knowledgeable. The public is increasingly adopting the biomedical model of mental illness, for instance, accepting the idea that psychiatric disorders have biological causes.

Furthermore, the idea that people are personally responsible for mental illness has receded. For example, the public is less likely to attribute alcohol abuse to personal character or weakness, accepting it, at least in part, as a disease. In short, the argument goes, science and culture can and will evolve together, together fomenting a medical approach. Whatever misconceptions the public had in the past, they are merely reflections of an imperfect understanding, which can be remedied with education.

THE FRAMEWORK OF THE DIAGNOSTIC SYSTEM In this book, I ask us to take a step back. Let me be clear about what I mean.

I will not ask us to ignore fifty years of progress. In fact, this book will discuss the contemporary science of psychiatric disorders in some detail and with approval. Nor will this book ask us to entertain the possibility that a much earlier era was, in some sense, a more tolerant one. Michel Foucault

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famously questioned whether the modern approach to psychiatric disorders was superior to the premodern one, wondering, in particular, whether regarding a psychiatric disorder as an illness was truly better than regarding it as, say, a product of divine intervention or as simply an unremarkable expression of the natural order.11 Nor is this book another critique of the DSM, at least not in a narrow sense. To be sure, I will review the controversies surrounding the DSM up to its latest iteration, but I do so not to argue that one side of a debate is superior to another but rather to illustrate how the form of the controversies surrounding the DSM has remained consistent over time. In addition, I also hope to show how some debates regarding the best classifications rest more on differences in first principles than on differences in empirical matters. In this way, this book will focus on the social, cultural, and scientific conditions that have set the stage for prolonged controversy, whether in earlier eras, in the present one, or, in all likelihood, in future eras as well. Another way to put this is to say this book adopts a more meta approach to the issue of classification, casting a wide eye on the many different parties and interests involved.

This book seeks to answer three related questions: why the classification of psychiatric disorders is so difficult, why it is necessary to classify in the first place, and what problems (and solutions) follow from the kinds of classifications we create. Answering these questions requires a capacious and multidimensional approach, which this book advances in a couple ways. For one, it explores definitions of mental illness from the standpoint of different stakeholders. It looks at what diagnostic criteria are and how they were developed, focusing naturally on the DSM. It also explores how clinicians think about psychiatric disorders. It then explores how scientists think about mental illness. At the same time, though, this book takes seriously what the public thinks about mental illness. Indeed, this book takes as its starting point that these different standpoints—from the lay to the expert, the impressionistic to the scientific, and the general to the specific—cannot be entirely segregated. The science of psychiatric disorders, for example, proceeds from how clinicians define disorders. And controversies surrounding how the public understands mental illness have corollaries in debates surrounding how scientists conceptualize mental illness. Mental illness sits

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within a remarkably large public sphere, and partly for that reason, it resists any sort of consensus.

At the same time, this book focuses on what different groups do with diagnoses. It focuses on the production of the DSM and the rules it contains, but, perhaps more importantly, it focuses on the reception of the DSM. Much has been made about how the DSM is useful, but answering the question of useful for whom and for what reasons makes the pragmatic aspects of the DSM more complicated and also makes appeals to crafting useful diagnostic criteria less compelling. This focus on how the DSM is received by different groups also helps us think about the various critiques of the DSM. Rather than assume the significance of formal diagnostic criteria a priori —that is, assume that the DSM is hegemonic in its influence across many domains—this book is concerned with how diagnoses are used and what significance or insignificance different groups attribute to them. Much of the debate surrounding the DSM naturally focuses on how it has been produced and the principles that have guided it. These controversies are ongoing, and there is no doubt they are significant. Controversies inhere to the text itself—what sentences and paragraphs are revised, what disorders are added, and what disorders are dropped—and for good reason. The DSM is regarded as the bible of modern psychiatry, and, befitting the analogy, many regard its criteria as sacrosanct. But a study of the Bible is not the same thing as a study of the church, the clergy, or the laity. This book focuses on the afterlife of the DSM and, in effect, the many different forms of apostasy.

It explores the social, clinical, and scientific consequences of the DSM critically and in detail, providing a ledger of sorts. It examines, for example, how clinicians actually use the DSM in their daily practice. It also explores what patients do when they receive a diagnosis (and, before that, how they decide whether to seek a diagnosis in the first place). We can study what psychiatric disorders truly are, and we can debate what they ought to be, but it is important not to overlook the actual consequences of formal diagnostic criteria as they are written. In this book, I will try to provide a more complete ledger of these consequences, both positive and negative, and in so doing I hope to address whether our fears regarding the DSM (not to mention our hopes) are realized or not.

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THE STRUCTURE OF THE CHAPTERS The structure of the book will play an important role in the development of my argument. The book starts in the next chapter by exploring the origins of the DSM, focusing in particular on its third revision. It will also consider the most recent revision, the fifth (with periodic mention of the others), but it focuses on the third because that revision set the form for the revisions that followed. In chapter 3, I will explore the descriptive science of psychiatric disorders as those disorders are defined in the DSM, followed in chapter 4 by the various proposals regarding how best to revise the DSM further in light of what that descriptive science revealed. This sequence implies a certain circularity between classification and science, and these chapters will elaborate on their imperfect and recursive interface in some detail. As a way of thinking about this problem, most of my discussion will focus on the principles, goals, and intentions of a classification system like the DSM. Then I dig deeper. In chapters 5 through 8, I will turn to the reception of the DSM: not what diagnoses are in description or intent but how they operate in actuality and practice. In this regard, I will begin with a natural starting point, discussing how mental health professionals use the DSM. There is no doubt that clinicians are interested in providing accurate diagnoses and that patients, too, are interested in learning exactly what is wrong with them. The DSM is critical to this task and so helps satisfy patients and clinicians alike. Yet mental health professionals do not use the DSM with perfect fidelity. The relationship between the use of mental health services and whether patients actually meet the formal diagnostic criteria for a psychiatric disorder is quite weak. Furthermore, clinicians tend to depart from formal diagnostic criteria in predictable ways, premised on a prototype they have in mind and not necessarily the sort of prototype detailed in the DSM. In this way, the DSM is not a binding document when it comes to clinical practice, although it is, nonetheless, a powerful one.

I turn in chapter 6 to how the public uses the DSM as well as to how it uses psychiatric concepts more generally. In this vein, I will discuss public beliefs about mental illness. I will also discuss how the public comes to

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regard diagnoses—which are essentially only names—as explanations. The work of a diagnosis—the meaning it harbors and the light it sheds—is significant for the public. Diagnoses illuminate experiences, and they help create new identities for individuals. But there is a potential shadow falling behind the light. Some observers, for example, fear that formal diagnostic criteria can artificially create the disorders they are merely meant to describe. They worry, for instance, about false epidemics, the problem of false positives, and diagnostic creep. Furthermore, some fear the DSM has created an overly therapeutic culture, one intolerant of individual differences and that incorrectly regards social problems as medical ones. Although most sociologists no longer regard labels as the central cause of mental illness, labels do play a role in how mental illness is experienced. For instance, clinical diagnoses of autism have increased precipitously over time. Has the “true” prevalence of autism increased as well? The use of antidepressants has, likewise, increased much more than the prevalence of depression would seem to have increased. How are we to regard these facts? Have the diagnostic criteria for mental illness somehow been unleashed into the larger culture, encouraging the encoding of normal suffering as full-blown illness?

Can the profession of psychiatry no longer contain its diagnostic authority?

It is important to be precise in our discussion of these issues. Th is book will entertain the possibility of labeling, as well as related issues such as looping, but it will do so in light of empirical evidence. The public certainly uses psychiatric diagnoses—in fact, the language of formal psychiatric nomenclature is suff used throughout popular culture, and the ascendance of psychiatric thinking can be linked directly to the publication of the DSM—but it is not clear that the public is unequivocally enthusiastic about diagnoses or that it embraces the DSM without qualification.

Chapter 7 explores how scientists use the DSM. Although earlier and later chapters explore this issue as well, chapter 7 focuses on how scientists have approached the dilemma stemming from both using the DSM as a requisite tool for their research and recognizing its many limitations. This chapter, then, provides a more focused account of the use and misuse of the DSM in scientific settings, rather than a report of the findings of science, as discussed in chapter 3.

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In chapter 8, I move to the broadest possible level—I explore how cultures use psychiatric diagnoses. Any discussion of culture is, of course, related to a discussion of the public—a culture is, after all, made up of people—but I intend to show how cultures operate with their own prerogatives and interests, many of which are independent of the mission of the DSM. Scientists frequently talk about how the DSM “reifies” diagnostic criteria, creating disorders that appear real in a formal sense but for which the underlying foundation is weak. Institutions perform a lot of the work of reification, and it is important to understand how they do so. More generally, though, diagnoses serve a variety of functions for a culture. They demarcate who is responsible for addressing certain behaviors. They shape how distress is expressed and determine which are regarded as the most credible symptoms of a disorder.

They also, in some instances, serve as a conduit for the expression of power.

In chapter 8 I explore the consequences of the DSM for how cultures think about and write about suffering.

The next two chapters turn to the contemporary science of psychiatric classification, discussing, in this case, something more than descriptive science: I discuss what science has to say regarding what psychiatric disorders might actually be. Chapter 9 provides a broad overview of the natural and social-scientific evidence regarding psychiatric classification, and chapter 10 discusses why searching for more “valid” psychiatric classifications is so difficult and why the issue of validity is unlikely to be resolved using even the best empirical and scientific tools. Chapter 11 ends with a synthetic overview of the contradictions of the diagnostic system. It also provides principles for thinking about the next revision of the DSM. Proceeding step by step across these different aspects of psychiatric classification is useful for illustrating a number of things. For one, it illustrates the sharp discontinuity between what we intend psychiatric diagnoses to accomplish and what they actually do. Furthermore, it illustrates where the controversies surrounding the DSM come from and, ultimately, why they are unlikely to be resolved any time soon. I regard the actors described in these chapters as composing an ecology of diagnosis, in reference also to how these actors interact (or not) with one another.12 The controversies surrounding psychiatric disorders reflect, I will argue, the contradictions and

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tensions embedded in this ecology and the inability of any single classification system to resolve all of these tensions simultaneously. I will also argue that this ecology explains why a focus on a single sector is incomplete. For instance, a focus on the science of psychiatric disorders will not necessarily produce insights that lend themselves to better revisions of the DSM, especially insofar as different actors have very different views about what a “valid” diagnosis looks like. Validity, unfortunately, is not given in nature, revealed once and for all when we discover the right tools. On the fl ip side, the criteria provided in the DSM are used by clinicians but do not always provide diagnoses that are appropriate for science. Controversies flow from other points of intersection as well. People rely on psychiatric diagnoses to make sense of their experiences, but formal diagnoses do not always serve this purpose well. Despite the promise of a more objective view of mental illness, for instance, scientific progress is not producing a uniformly more tolerant public. A genetic approach to psychiatric disorders serves science well, but the public sometimes becomes less tolerant when it regards mental illness as deeply rooted in biology.

My emphasis on the ecology of diagnostic classification has other implications. Although many have critiqued the power of the DSM, referring to its “tyrannical” aspects (if still couching it as a benevolent tyrant), I intend to show that the DSM is nestled in a system of checks and balances that transmute and blunt its influence.13 The DSM is fundamentally useful, even if it is not perfectly valid relative to the biological entities we can now identify. This implies a good deal of flexibility and uncertainty in classification.

But the fact that clinicians, scientists, and the public use diagnostic classifications in their own particular ways and to their own ends is not in itself a problem. Indeed, it ought to alleviate some of the pressure the authors of the DSM—or even the scientists who try to help them craft better criteria—feel to derive the best possible classification over all possible considerations.

Furthermore, there is incommensurability embedded in how clinicians, scientists, and the public use psychiatric diagnoses. It is difficult to envision a time when science might serve as the ultimate arbiter of these differences and resolve all the contradictions in a way that satisfies everyone.

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An emphasis on the ecological setting of diagnoses also highlights the importance of judgment, something that has perhaps been elided in recent years. Despite the optimism surrounding genes and neuroscience, the contemporary science of psychiatric disorders does not provide unambiguous insights regarding the nature of psychiatric disorders. Nor does it absolve scientists and clinicians of the difficult task of making decisions about what psychiatric disorders are. Decisions of this sort involve many considerations.

They involve values, competing interests, and public interest. They also involve choices. We might regard science as the unassailable authority on what psychiatric disorders are, but it is difficult or impossible to split scientific evidence from all the other issues that psychiatric disorders intersect with.

It is difficult, for instance, to impose objective criteria over symptoms that are, in their essence, subjective. It is also difficult to produce accurate diagnostic criteria when validity can be evaluated in numerous ways. Some recent controversies reflect an implicit acknowledgment of this tension even as scientists have seemingly sought to obviate it. For instance, the recently proposed Research Domain Criteria (RDoC), emerging from the National Institute of Mental Health, is explicit in attempting to cleave the science of psychiatric disorders—that is, attempts to understand “real” disorders based on biological and neurological evidence—from the normative aspects of psychiatric disorders—that is, discussions of values or debates regarding what is or is not “normal.” The RDoC also attempts to minimize some of the cultural aspects of the DSM, including, especially, its dependence on subjectively reported symptoms. In particular, the RDoC attempts to circumvent reliance on verbal reports, such as “I feel depressed,” by using neuroanatomical traces of that emotion instead. But such efforts raise larger questions about what we as a society are prepared to regard as the most authoritative signals of experience. Prioritizing the signals of the brain over the reports of a person involves complex tradeoffs.

There is a reason the title of this book refers to the diagnostic system. As I am sure the reader has already discerned, the title is a double entendre: When most people think of a diagnostic system in the context of mental illness, they almost certainly think of the DSM. But in using the title, I am hoping

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for an additional connotation: By diagnostic system I am referring to how the entire diagnostic enterprise, including but not limited to the DSM, is situated in a complex social and cultural ecology. A system, too, implies some sort of organization or persistence, even when haphazard in appearance.

Some other terms are useful to define up front, in part because their definitions get to the heart of the matter. A diagnosis refers not only to the formal diagnostic criteria that define a psychiatric disorder but also to the application of those criteria to a person. The word is a noun, but it can be converted to a verb. A person receives a diagnosis, and a clinician diagnoses a disorder. Other terms refer to psychiatric classification per se and not to its application.14 Ultimately I am interested in describing classification, that is, the procedures used for constructing categories of psychiatric disorder. A classification system provides a framework for organizing different entities.15 A taxonomy is a more precise term. It refers to the theory that guides classification, allowing entities to be arranged according to deeper features of similarity. It refers, then, to the logic of a classification system or to the abstract principles that guide it. The term nosology is the clinical equivalent of the more general concept of a taxonomy. It refers to the classification of diseases in particular, rather than the many other entities that can be organized under a taxonomy, such as species. It turns out, though, that even seemingly clear taxonomies, like those for species, struggle with some of the same issues as the DSM. Defining these terms foreshadows some of the distinctions that will later emerge as important. The next chapter, for example, describes the DSM as a classification system. It discusses the DSM ’s underlying philosophy and principles. Yet I want to be clear that even as a classificatory system the DSM is far from a formal taxonomy. The theory underlying the DSM is generally quite superficial, even though the principles guiding it were well thought out and well intentioned. The next chapter also describes the process by which the DSM has been written and revised. Here, too, the lesson is less one of gradual improvement than of ongoing renegotiation among interested parties. Although the manual is now more than thirty years old, a review of the DSM-III is the best place to start a discussion of the contested ontology of psychiatric disorders.

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