Classification of mental disorders

The classification of mental disorders is also known as psychiatric nosology or psychiatric taxonomy. It represents a key aspect of psychiatry and other mental health professions and is an important issue for people who may be diagnosed. There are currently two widely established systems for classifying mental disorders: The classification of mental disorders is also known as psychiatric nosology or psychiatric taxonomy. It represents a key aspect of psychiatry and other mental health professions and is an important issue for people who may be diagnosed. There are currently two widely established systems for classifying mental disorders: Both list categories of disorders thought to be distinct types, and have deliberately converged their codes in recent revisions so that the manuals are often broadly comparable, although significant differences remain. Other classification schemes may be in use more locally, for example the Chinese Classification of Mental Disorders. Other manuals have some limited use by those of alternative theoretical persuasions, such as the Psychodynamic Diagnostic Manual. The widely used DSM and ICD classifications employ operational definitions. There is a significant scientific debate about the relative validity of a 'categorical' versus a 'dimensional' approach to classification, as well as significant controversy about the role of science and values in classification schemes and the professional, legal and social uses to which they are put. In the scientific and academic literature on the definition or categorization of mental disorders, one extreme argues that it is entirely a matter of value judgments (including of what is normal) while another proposes that it is or could be entirely objective and scientific (including by reference to statistical norms); other views argue that the concept refers to a 'fuzzy prototype' that can never be precisely defined, or that the definition will always involve a mixture of scientific facts (e.g. that a natural or evolved function isn't working properly) and value judgments (e.g. that it is harmful or undesired). Lay concepts of mental disorder vary considerably across different cultures and countries, and may refer to different sorts of individual and social problems. The WHO and national surveys report that there is no single consensus on the definition of mental disorder, and that the phrasing used depends on the social, cultural, economic and legal context in different contexts and in different societies. The WHO reports that there is intense debate about which conditions should be included under the concept of mental disorder; a broad definition can cover mental illness, mental retardation, personality disorder and substance dependence, but inclusion varies by country and is reported to be a complex and debated issue. There may be a criterion that a condition should not be expected to occur as part of a person's usual culture or religion. However, despite the term 'mental', there is not necessarily a clear distinction drawn between mental (dys)functioning and brain (dys)functioning, or indeed between the brain and the rest of the body. Most international clinical documents avoid the term 'mental illness', preferring the term 'mental disorder'. However, some use 'mental illness' as the main overarching term to encompass mental disorders. Some consumer/survivor movement organizations oppose use of the term 'mental illness' on the grounds that it supports the dominance of a medical model. The term 'serious mental impairment' (SMI) is sometimes used to refer to more severe and long-lasting disorders while 'mental health problems' may be used as a broader term, or to refer only to milder or more transient issues. Confusion often surrounds the ways and contexts in which these terms are used. Mental disorders are generally classified separately to neurological disorders, learning disabilities or mental retardation. The International Classification of Diseases (ICD) is an international standard diagnostic classification for a wide variety of health conditions. The ICD-10 states that mental disorder is 'not an exact term', although is generally used '...to imply the existence of a clinically recognisable set of symptoms or behaviours associated in most cases with distress and with interference with personal functions.' Chapter V focuses on 'mental and behavioural disorders' and consists of 10 main groups: Within each group there are more specific subcategories. The WHO is revising their classifications in this section as part of the development of the ICD-11 (revision due by 2018) and an 'International Advisory Group' has been established to guide this.