Diagnostic and Statistical Manual (DSM)

The Diagnostic and Statistical Manual of Mental Disorders, or DSM, is an official classification system of mental disorders used in the United States and by many health professionals around the world. Published by the American Psychiatric Association, the DSM is an evolving text that is periodically revised to reflect the most contemporary knowledge regarding psychological disorders. Since its inception in 1952, this handbook has undergone a series of revisions (DSM-II, DSM-III, DSM-III-Revised, DSM-IV, and DSM-IV-TR).

Reflecting the human penchant for organizing and categorizing, the DSM contains comprehensive descriptions of several hundred psychiatric disorders, ranging from relatively minor adjustment-related issues to severe, persistent, and disabling conditions. In recent editions of the DSM, researchers have rigorously attempted to establish a valid and reliable diagnostic system. To this end, numerous task forces were appointed to ensure that the diagnoses reflect distinct clinical phenomena that can be applied to individuals showing a particular constellation of symptoms.

Early versions of the DSM were criticized for their identification with a psychodynamic theoretical orientation. The authors of recent versions purposely adopted an atheoretical approach to diagnosis, whereby descriptions of psychological disorders represent observable phenomena rather than formulations of possible etiologies. In this respect, the DSM provides practitioners and researchers with a common language for delineating disorders, and it ensures that the diagnostic labels represent agreed-upon clinical phenomena.

Epistemological Assumptions and Definition of Mental Disorder

The DSM makes the assumption that mental disorders reflect an external reality. While its creators and contributors acknowledge that mental disorders are imperfect constructions, they also posit that such constructions yield considerable practical and heuristic value (e.g., guiding clinical practice and treatment planning). To reap such benefits, the term mental disorder requires a meaningful operational definition. However, like many constructs in science and medicine, a consistent and all-encompassing definition remains elusive. While no definition will adequately address all elements that may distinguish abnormal from normal, the DSM makes a comprehensive attempt. According to the DSM, a mental disorder must reflect distress or disability that is present over a designated period of time and that affects the individual’s life enough to create clinically significant suffering, cause a significant decrease in normal functioning, or involve serious risk to the individual. Furthermore, these experiences must not simply reflect an expectable or culturally sanctioned response to an event, such as sadness related to the death of a loved one. Finally, irrespective of their etiology, the current difficulties must be conceptualized as manifestations of personal behavioral, psychological, or biological dysfunctions.

The Medical Model and Categorical Approach

Early in the evolution of the DSM, its creators attempted to establish a diagnostic system that was compatible with a broader worldwide medical taxonomy—that is, the International Classification of Diseases, Injuries, and Causes of Death (ICD) developed by the World Health Organization (WHO). Hence, the DSM adopts a medical model of diagnosis for which mental disorders, regardless of whether their etiology is biological or psychological, are viewed as “mental illnesses” requiring treatment. Furthermore, implicit in this model is the assumption that mental disorders comprise behavioral and psychological symptoms that form a distinct and definable pattern or “syndrome.” Thus, the creators of the DSM made a conscious choice to adopt a categorical taxonomy of mental illnesses. It is important to note, however, that the DSM makes no assumption that all mental disorders are discreet entities with absolute boundaries. Rather, it adopts a prototype model with several accommodations for the “fuzzier” diagnostic situations and for within-disorder heterogeneity. These accommodations include the use of severity specifiers and subtypes, general categories for clinically significant conditions that do not meet the specifications for more specific categories (but nonetheless require clinical attention), and polythetic criteria sets whereby diagnoses are made based on a proportion of endorsed criteria out of a larger criteria set. The DSM has also made special efforts to increase cultural awareness and sensitivity in diagnosis by including descriptions of cultural variations in manifestations of DSM disorders, an appendix of known culture-bound systems that are not included in the DSM nomenclature, and a guide for cultural formulation.

The Multiaxial System of Diagnosis

Over time, professionals have increasingly acknowledged that psychological disorders involve complex interactions of biological, social, and psychological factors. With this shift to a more holistic view of mental illness, or the biopsychosocial approach, clinicians and researchers have called for a more comprehensive approach to diagnosis. Consequently, authors of DSM-III accounted for this paradigm shift with the introduction of a multiaxial system of diagnosis. This system comprises five axes along which each individual is diagnostically evaluated. Each mental disorder in the DSM is diagnosed on either Axis I or II. The remaining three axes are used to characterize an individual’s physical health (Axis III), environmental and psychosocial stressors (Axis IV), and overall level of functioning (Axis V).

Axis I: Clinical Disorders and “V” Codes

The major clinical disorders, or syndromes, such as depression, schizophrenia, and bipolar disorder, are diagnosed on Axis I. Axis I also includes adjustment disorders, or extreme reactions to life events that would not normally be expected (e.g., prolonged depression following the loss of a job). Also located on Axis I are V codes that are used to acknowledge conditions that are not attributable to a mental disorder (e.g., academic problems, acculturation problems), but are the primary reason for seeking treatment. When these problems are evident, but not the primary focus of concern, they are noted on Axis IV.

Axis II: Personality Disorders and Mental Retardation

Personality disorders and mental retardation are diagnosed on Axis II. Personality disorders reflect the presence of pervasive, inflexible, and maladaptive behaviors, thoughts, and responses that interfere with normal interpersonal relationships and cause an individual considerable distress or impairment. An example is paranoid personality disorder where an individual is significantly suspicious and distrustful of other people and interprets their intentions as threatening and malevolent. This orientation to others is often so extreme that the individual has few close relationships.

Also located on Axis II is the diagnosis of mental retardation. Although not a personality disorder, mental retardation is considered a pervasive condition that has a significant influence on a person’s behavior, personality, and cognitive functioning. Of note, it is possible to have multiple diagnoses on Axis I and/or II to account for co-occurring conditions.

Axis III: General Medical Conditions

Practitioners use Axis III to document any physical complaints or medical conditions that may play a role in the individual’s psychological discomfort. For example, an individual suffering from panic disorder may also experience occasional asthmatic attacks in which he or she experiences respiratory distress. Given the dynamic interaction between these two experiences, it would be useful to be aware of both conditions when conceptualizing the case, developing a treatment plan, and communicating the case to other professionals.

Axis IV: Psychosocial and Environmental Problems

Practitioners use Axis IV to document stressors in the environment that may aggravate, exacerbate, or in some way relate to the individual’s current psychological functioning. Some examples include job loss, death of a family member, or a recent divorce.

Axis V: The Global Assessment of Functioning Scale

Axis V is used to document the practitioner’s overall judgment (on a scale of 1-100) of an individual’s level of psychological, social, and occupational functioning.

DSM Assessment

In addition to traditional diagnostic methods (e.g., clinical interviewing, objective and projective testing), several specific systems have been developed to facilitate DSM-based diagnosis. The most notable are the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I) and the Structured Clinical Interview for DSM-IV Axis II Disorders (SCID-II).

DSM Benefits

Although the creators of and contributors to the DSM acknowledge that its constructivist and categorical foundation has limitations, they also argue that it provides major benefits to the mental health field. Such benefits include (a) the promotion of effective communication among practitioners and researchers; (b) the facilitation of problem-identification, treatment, and prevention; (c) the facilitation of research into the etiology and treatment of specific mental conditions; and (d) the provision of a heuristic for teaching psychopathology and training practitioners on psychodiagnosis.

References:

American Psychiatric Association. (2000). Diagnostic and statistical manual of mental disorders (4th ed., Text rev.). Washington, DC: Author.
Fauman, M. A. (2002). Study guide to DSM-IV-TR. Washington, DC: American Psychiatric Press.
First, M. B., Spitzer, R. L., Gibbon, M., & Williams, J. B. W. (1996). Structured Clinical Interview for DSM-IV Axis I Disorders, Clinician Version (SCID-CV). Washington, DC: American Psychiatric Press.
First, M. B., Spitzer, R. L., Gibbon, M., & Williams, J. B. W. (1996). Structured Clinical Interview for DSM-IV Personality Disorders (SCID-II). Washington, DC: American Psychiatric Press.
Frances, A., First, M. B., & Pincus, H. A. (1995). DSM-IV guidebook. Washington, DC: American Psychiatric Press.
Frances, A., & Ross, R. (2001). DSM-IV-TR case studies: A clinical guide to differential diagnosis. Washington, DC: American Psychiatric Press.