0 Enhanced specificity for major and mild neurocognitive disorders. Given the explo- sion in neuroscience, neuropsychology, and brain imaging over the past 20 years, it was critical to convey the current state-of-the-art in the diagnosis of specific types of disor- ders that were previously referred to as the "dementias” or organic brain diseases. Bi- specific molecular genetic findings for rare variants of Alzheimer’s disease and Hun- tington’s disease have greatly advanced clinical diagnoses, and these disorders and others have now been separated into specific subtypes.
9 Transition in conceptualizing personality disorders. Although the benefits of a more dimensional approach to personality disorders have been identified in previous edi- tions, the transition from a categorical diagnostic system of individual disorders to one based on the relative distribution of personality traits has not been widely accepted. In
DSM-S, the categorical personality disorders are virtually unchanged from the previous edition. However, an alternative "hybrid" model has been proposed in Section III to guide future research that separates interpersonal functioning assessments and the ex- pression of pathological personality traits for six specific disorders. A more dimensional profile of personality trait expression is also proposed for a trait-specified approach.
0 Section 111: new disorders and features. A new section (Section III) has been added to highlight disorders that require further study but are not sufficiently well established to be a part of the official classification of mental disorders for routine clinical use. Dimen- sional measures of symptom severity in 13 symptom domains have also been incorpo- rated to allow for the measurement of symptom levels of varying severity across all diagnostic groups. Likewise, the WHO Disability Assessment Schedule (WHODAS), a standard method for assessing global disability levels for mental disorders that is based on the International Classification of Functioning, Disability and Health (ICF) and is ap- plicable in all of medicine, has been provided to replace the more limited Global As- sessment of Functioning scale. It is our hope that as these measures are implemented over time, they will provide greater accuracy and ﬂexibility in the clinical description of sessments.
0 Online enhancements. DSM-5 features online supplemental information.
Additional cross-cutting and diagnostic severity measures are available online (www.psychiatry.org/ dsm5), linked to the relevant disorders. In addition, the Cul- tural Formulation Interview, Cultural Formulation Interview—Informant Version, and supplementary modules to the core Cultural Formulation Interview are also included online at www.psychiatry.org/dsm5.
These innovations were designed by the leading authorities on mental disorders in the world and were implemented on the basis of their expert review, public commentary, and independent peer review. The 13 work groups, under the direction of the DSM-S Task
Force, in conjunction with other review bodies and, eventually, the APA Board of Trust- ees, collectively represent the global expertise of the specialty. This effort was supported by an extensive base of advisors and by the professional staff of the APA Division of Re- search; the names of everyone involved are too numerous to mention here but are listed in the Appendix. We owe tremendous thanks to those who devoted countless hours and in- valuable expertise to this effort to improve the diagnosis of mental disorders.
We would especially like to acknowledge the chairs, text coordinators, and members of the 13 work groups, listed in the front of the manual, who spent many hours in this vol- unteer effort to improve the scientific basis of clinical practice over a sustained 6-year pe— riod. Susan K. Schultz, M.D., who served as text editor, worked tirelessly with Emily A.