DIAGNOSTIC AND STATISTICAL MANUAL OF MENTAL DISORDERS

The Diagnostic and Statistical Manual of Mental Disorders (DSM) represents the most influential effort in the field of mental health to identify psychological and psychiatric abnormalities for the purposes of treatment. The extent to which this effort has been pursued in a rigorously scientific manner, and the ethical issues surrounding the distinction between normal and abnormal mental functioning, are important questions for clarification and debate.

The DSM, which has been compiled and published by the American Psychiatric Association (APA) since its first publication in 1952, is intended to serve as a standard tool for mental health professionals in the diagnosis of mental illness. In addition to providing the field with a definition of the term mental disorder, the fourth edition of the manual (DSM-IV-TR; APA 2000) contains a catalog of the clinical symptoms of 365 different mental disorders (for example, obsessive–compulsive disorder, borderline personality disorder), which are organized into sixteen major diagnostic classes (such as anxiety disorders, personality disorders, and so on).

With each subsequent edition, the classifications provided by the DSM have become more widely referenced in the field of psychopathology. In addition, the DSM system of diagnosis has become increasingly central to the communication between mental health professionals and those outside the field, such as lawyers, insurance companies, and the media. Nevertheless, the system remains highly controversial, even among those who have contributed to its development. Some of this controversy surrounds the general issue of whether or not the diagnosis of mental illness is a scientific endeavor at all. More specific criticism has also been leveled, however, at the specific approaches the DSM has taken over its history to describe or explain mental disorders. In both cases, the debate over the DSM has often raised fundamental questions about the nature and diagnosis of mental illness.

The Origins and History of the DSM

As Gerald N. Grob (1991) has detailed, psychiatrists of the early 1900s were largely uncomfortable with the idea that the symptoms of mental illness could be broken down into any meaningful classification scheme. The professionals of this period tended to view the individual case as highly unique and subject to a wide variety of interrelated personal and environmental variables. Various classification schemes were proposed between 1900 and 1920, including a collaborative effort of the U.S. Bureau of the Census and the existing version of the American Psychiatric Association that produced a taxonomy of twenty-two categories of mental disorder, most of which were predicated on a particular form of biological abnormality. Such systems, however, were largely irrelevant in clinical practice or research. Instead, they served primarily to provide gross survey categories for hospitals and local governments to use in the compilation of statistics on rates of mental illness among different demographic and ethnic groups and on standards of care across different communities.

During World War II, however, mental health professionals began caring for large numbers of patients (i.e., soldiers) who did not require long-term confinement in a hospital. These patients showed psychophysical, personality, and acute stress disorders that were not well documented and that added significant variety to the existing classifications of mental illness. Inspired by these circumstances, the APA formed a committee of experts to establish a diagnostic system that expanded upon systems developed for the U.S. armed forces and adapted the international statistical classification of diseases, injuries, and causes of death, developed by the World Health Organization, for use in the United States. This process involved a significant expansion and reorganization of the existing systems and culminated in the publication of the first DSM (DSM-I) in 1952. The DSM-I (and the subsequent DSM-II, published in 1968) represented a major turning point in the nature and purpose of a taxonomy of mental disorders. For one thing, it was the first attempt to standardize psychiatric diagnoses according to a particular theory of mental illness (that is, psychoanalytic theory). Moreover, the DSM was proposed to advance the science, and not just the administration, of mental health services. By providing mental health professionals with a common diagnostic language and by grounding the descriptions of the disorders in the prevailing psycho-analytic theory, the DSM was intended to further stimulate and synthesize research into the nature of mental illness.

These first two editions of the DSM, however, were not received with unequivocal support. The two primary complaints mental health professionals voiced against the DSM concerned the lack of evidence for the distinctions it made among various disorders and the small number of experts involved in determining the classification scheme. The reliance on psychoanalytic concepts was also increasingly questioned given the rise of more empirical and behavioral approaches in clinical settings. In response the APA took a distinctively different approach to developing the third (DSM-III, 1980) and fourth (DSM-IV, 1994) editions. For each of these editions, expert researchers and clinicians were organized into work groups for each category of disorders (e.g., anxiety disorders, substance-abuse disorders). These groups conducted reviews of the available literature to determine whether or not the criteria for each disorder and the distinctions among disorders were supported by empirical evidence. Although the findings from the work groups continued to be compiled and reviewed by committee, the emphasis on research increased both the objectivity of the decision-making process and the number of professionals who could influence the final product. The manual also became accessible to a wider range of professionals by abandoning a central theoretical perspective and adopting a focus on clinically observable symptoms such as thoughts of suicide or repetitive behaviors.

Current Issues in the Development and Application of the DSM

The primary purpose for the development of the DSM has always been its use as a clinical tool for guiding the assessment and treatment of mental disorders. Perhaps the greatest strength of the DSM is its usefulness in differential diagnosis. For example, a patient's complaint of feeling down or depressed can be evaluated in light of other clinical symptoms that are present and compared with the criteria for disorders such as Major Depressive Episode and Adjustment Disorder with Depressed Mood. Although disorders such as these share some common features, distinctions among them with regard to etiology (cause) and prognosis may provide important guidance for treatment planning. In fact, some clinicians argue that the future of mental health as a science depends heavily on the ability of professionals to distinguish among treatments that are or are not effective for specific diagnoses. Such an approach ultimately leads to the matching of treatment with diagnosis based on support from available research.

An important problem with such an approach, however, is that patients with distinctly different symptoms and clinical presentations can receive the same diagnosis. In the DSM-IV, for example, each disorder is characterized by a set of equally weighted criteria. Patients need not meet all criteria for a given disorder in order to fit the diagnosis. This flexibility allows for more reliable diagnosis across clinicians, but it can also lead to minimal overlap in symptoms between any two patients with the same diagnosis. Often, symptoms that these patients do not share play a major role in treatment planning and clinical management.

A similar problem concerns the frequency with which patients meet criteria for more than one disorder at a given time (known as comorbidity). As Lee Anna Clark, David Watson, and Sarah Reynolds (1995) have noted, more than half of all individuals with a DSM diagnosis also meet criteria for another disorder. In many cases, the presence of a second disorder is a significant issue that has a dramatic effect on a patient's response to a given treatment.

A third problem with the use of the DSM in treatment planning is the lack of a coherent theoretical framework for understanding the causes and progressions of the various disorders. This limitation is ironic, given that a descriptive, symptom-focused approach was deliberately adopted in the DSM-III and DSM-IV to make the manual accessible to a range of professionals with different theoretical orientations. Clinicians inevitably rely on a particular theoretical framework in assessment and treatment planning, however, and so a purely descriptive manual cannot help but appear removed from reality in clinical settings.

Beyond its clinical utility, the DSM has also been developed to facilitate research and communication among professionals regarding the nature of mental illness. Prior to the development of the DSM, clinicians developed colloquial classification schemes that did not generalize far beyond their immediate setting. Although many professionals of the time considered such an approach to be unavoidable, they also recognized the difficulties this posed for efforts to increase or disseminate their base of knowledge. The DSM has certainly increased systematic research into mental illness and placed that research in a framework that is accessible to a broader scientific community. A prominent example is the dramatic increase of research in personality disorders that has occurred because these disorders were given special emphasis in the DSM-III (Widiger and Shea 1991).

The question remains, however, whether this proliferation in research has resulted in any real increases in scientific knowledge concerning mental illness. For instance, critics have noted that as the DSM classifications have become more widely adopted, they have begun to take on the nature of assumptions rather than scientific problems to be investigated. Thus, researchers may rely on DSM criteria instead of independent, theoretically driven criteria in selecting research participants. In this way, the DSM has become a somewhat self-perpetuating framework.

In addition, it is important to keep in mind that the ultimate decisions about making changes to the manual are not purely empirical exercises. Such decisions must appeal to fundamental assumptions about principles concerning the nature of mental illness and the goals of the system itself. Along these lines, Arthur C. Houts (2002) has argued that it is unlikely that the continual expansion of the DSM from 106 disorders in 1952 to 365 disorders in 1994 represents real scientific advance in the ability to detect and diagnose mental illness. In particular, this expansion of labels has not occurred alongside the necessary solidification of a limited number of "covering" or "synthesizing" laws that would explain how all these new disorders relate to one another. A more specific and highly publicized example of this problem concerns the removal of homosexuality as a mental disorder in the third edition of the DSM. Regardless of whether or not homosexuality should be included in the DSM as a mental disorder, even the leadership of the revision process has admitted that the decision was ultimately based more on social pressures than on the weight of scientific evidence (Spitzer, Williams, and Skodol 1980).

A third central purpose for the development of the DSM concerns the justification of professional services and judgments. Particularly in the arenas of insurance reimbursement and legal proceedings, mental health professionals are expected to demonstrate that their evaluations and treatment plans meet some standard of common practice in the profession. With respect to insurance, however, it continues to be difficult to justify treatment decisions based on a particular diagnostic picture. Because of the heterogeneity of patients who can share a given diagnosis and because the DSM continues to explicitly require clinical judgment in assigning a diagnosis and planning treatment, the assignment of a particular diagnosis to a patient can have very little impact on the clinical services provided to that patient. Furthermore, clinicians often use DSM diagnoses for purely instrumental reasons (e.g., to promote or protect the relationship with the patient, to obtain services from a resistant insurance provider). In a common example, clinicians, in order to avoid stigmatizing or scandalizing a patient, will often diagnose the person with adjustment disorder (which connotes a more transient and normative reaction to stress) instead of a more serious disorder even though the patient meets the criteria for the latter. With regard to the courts, mental health professionals cannot assume that a particular DSM diagnosis of mental illness bears any correspondence to the legal definition of "mental disease" or "mental defect." Thus, questions of diagnosis are often abandoned altogether in the courtroom in favor of more straightforward comparisons of symptoms and states of mind with legal definitions of sanity.

Future Directions for the DSM

Shortly after publication of the DSM-IV, clinicians began expressing hopes that future editions would address several fundamental flaws in the current classification scheme, in addition to those mentioned above. Perhaps the most common desire is to move away from categorical (i.e., yes or no) diagnosis of mental disorders and toward a system of rating patients on a small number of basic, personological dimensions (e.g., personality traits). Proponents argue that such a system would have greater value in guiding differential diagnosis, would help consolidate the growing number of disorders, and would more validly reflect the dynamic nature of the individual. A less radical revision that, presumably, would also reduce the degree of disparate diagnoses is John F. Kihlstrom's (2002) proposal that the current phenomenological groupings of symptoms be replaced with diagnoses based on laboratory findings such as characteristic cognitive or affective deficits. Finally, Thomas A. Widiger and Lee Anna Clark (2000) recommend that greater attention be paid to the most basic element of the diagnostic system: the establishment of meaningful boundaries between normal and abnormal psychological functioning. Common to all these proposals is a need for the DSM to develop a more unified and coherent framework of mental illness that is more validly rooted in the fundamental nature of the human person.

Central to the ongoing debates surrounding the DSM, then, is the role of values and metaphysical assumptions in defining psychological normality and, thus, providing a foundation for the identification and treatment of abnormality. Whereas empirical science may be invaluable in describing the mental, emotional and physical processes underlying psychological disorders, interpretation of these descriptions inevitably proceeds from a framework containing statements about the nature of human abilities, the kind of life worth living, and the ideal form of relationships among persons or between persons and their environment. As Daniel Robinson (1997) has argued, any theory of psychological disorder and therapy that is divorced from these questions fails to answer the question, "therapy for what?" because it will fail to account for the kind of healing or remediation that is necessary. These kinds of metaphysical issues, which are also assuming an increasingly central role in the ethics of the biological and genetic sciences, bring into clearer relief the nature and limits of a scientific attempt to identify problems or deficiencies in the psychological life of persons.

CARLETON A. PALMER

SEE ALSO Homosexuality Debate;Psychology.

BIBLIOGRAPHY

American Psychiatric Association (APA). (2000). Diagnostic and Statistical Manual of Mental Disorders: DSM-IV-TR, 4th edition, text revision. Washington, DC: Author. This most recent revision updates the text of the DSM-IV to include the results of research conducted after 1992. The revision is intended to maintain the usefulness of the DSM as an educational resource between major editions.

Clark, Lee Anna, David Watson, and Sarah Reynolds. (1995). "Diagnosis and Classification of Psychopathology: Challenges to the Current System and Future Directions." Annual Review of Psychology 46: 121–153. The authors review the purposes of a diagnostic taxonomy and consider alternatives to the current, descriptive approach. Research failing to support categorical diagnosis of psychopathology is highlighted.

Grob, Gerald N. (1991). "Origins of DSM-I: A Study in Appearance and Reality." American Journal of Psychiatry 148(4): 421–431. Examines the social and political context in which the DSM-I was developed.

Houts, Arthur C. (2002). "Discovery, Invention, and the Expansion of the Modern Diagnostic and Statistical Manuals of Mental Disorders." In Rethinking the DSM: A Psychological Perspective, ed. Larry E. Beutler and Mary L. Malik. Washington, DC: American Psychological Association. Analyzes the assumption that the proliferation of DSM diagnostic labels across editions represents actual scientific progress in the assessment and differentiation of psychological disorders.

Kihlstrom, John F. (2002). "To Honor Kraepelin … : From Symptoms to Pathology in the Diagnosis of Mental Illness." In Rethinking the DSM: A Psychological Perspective, ed. Larry E. Beutler and Mary L. Malik. Washington, DC: American Psychological Association. Argues that a taxonomy based on laboratory observations would advance the science of psychopathology and return the practice of psychological diagnosis to its historical roots.

Robinson, Daniel N. (1997). "Therapy as Theory and as Civics." Theory and Psychology 7(5): 675–681. The author suggests that fitness for the moral and civic aspects of human life provides the grounding for any theories of mental disorder and any attempts at psychotherapy.

Spitzer, Robert L., Janet B. W. Williams, and Andrew E. Skodol. (1980). "DSM-III: The Major Achievements and an Overview." American Journal of Psychiatry 137(2): 151–164. Leaders from the task force on DSM-III describe the origins of its development and the reasons for the major transition toward an atheoretical approach to defining and classifying mental disorders.

Widiger, Thomas A., and Lee Anna Clark. (2000). "Toward DSM-V and the Classification of Psychopathology." Psychological Bulletin 126(6): 946–963. Discusses the more significant issues of disagreement and debate surrounding the DSM-IV and recommends continued exploration of alternatives to the current perspective.

Widiger, Thomas A., and Tracie Shea. (1991). "Differentiation off Axis I and Axis II Disorders. Journal of Abnormal Psychology 100(3): 399–406. Suggests that the distinction between personality and symptomatic disorders first introduced in DSM-III ignores important relationships between them and instances of significant overlap in symptomatology.